1912-1915

 

Voyage down the São Francisco river

and some of its tributaries between

Pirapora and Juazeiro*

 

(Studies carried out at the request of the Inspectoría de Obras

Contra a Seca, Dr. Arrojado Lisboa, Director)

When our journey began, the dry season was already well established. With only one or two exceptions, there was no rain during the whole voyage. Consequently, the banks of the river became more and more arid, until, upon arriving at Juazeiro, we found the outskirts looking like a desert, because the vegetation had been burnt by the sun and many trees were devoid of leaves. Insect-life and other small animals decreased in the same proportion. Our collecting suffered much from these conditions since the region traversed would undoubtedly have been richer if the season had been more favorable, although this region is relatively poor. Under the circumstances, the only larger collection we made was of moths, mostly small ones, which were caught on board at night when they were attracted by the carbide lamps we set up. They were accompanied by other insects, Neuroptera and Diptera, with aquatic larvae, and among these, a large number of mosquitoes, mostly belonging to a few common species. Besides these, some other blood-sucking Diptera were obtained at great cost. The whole collection, which will be discussed separately, was small and composed mainly of known species. Nevertheless, we had the opportunity to make some rather interesting biological observations in regard to some of these species.

Preservation of the larger animals that might have been obtained during this rapid trip was hampered by the loss of a box with preserving fluids. As it had been forwarded in time, we went on hoping to receive it eventually, but we were disappointed. Collecting was thus restricted to dry pelts and to a few reptiles and fish. We also felt the loss of other substances needed for microscopic use. The box never reached us and was utterly lost. To compensate for this, a fairly large herbarium was made. The flora of this region, although not rich on account of the droughts, has rather special characteristics, which are of considerable interest. There are many plants adapted to sandy soil and some that grow on pure sand. On the other hand, there are a large number of more or less aquatic plants.

Our observations on the diseases of man and of domestic animals confirmed our assumptions as to their lack of variety. The cases of Chagas’ disease, which were of special interest to us, decreased as we approached the borders of the state of Minas Gerais; in the state of Bahia there were almost none at the edges of navigable rivers. Proportionately, the main transmitter, Triatoma or Conorhinus megistus, disappeared even more rapidly. Triatoma sordida was abundant on the banks of rivers, both in Minas and in Bahia, but the distribution of the disease did not coincide with its presence. If, on the one hand, one cannot deny categorically that it can transmit the trypanosome, everything indicates that it is rarely infected. Human blood does not seem to attract it especially, and it often prefers chicken coops to human dwellings. However, this species is generally known, which is not the case of Triatoma megista, a species completely unknown in quite extensive zones. Besides these, we found a third species, T. maculosa, but obtained only one specimen of it.

Another very interesting problem of regional pathology is endemic goiter. As many cases are found among persons infected with coreotrypanosomiasis, goiter found in this region has been attributed solely to Chagas’ disease. It should be mentioned that lesions of the thyroid are more common than the other, certain prodromata or symptoms of trypanosomiasis, though the coincidence between swollen glands, especially in the neck, is fairly frequent. Otherwise, lesions of the thyroid cannot be clearly distinguished from ordinary endemic goiter. All along the São Francisco River, the whole population habitually drinks river water, often exclusively, so that one might easily attribute goiter to it. However, the number of goiters decreases as one travels down the river, until practically disappearing among people who have never been away. Of course this observation, which also applies to other rivers, does not necessarily preclude the possibility that the river water may contain a substance or organism that can produce goiter, but neither does it favor such a supposition. Indeed, it might instead point to the absence, in the upper reaches, of a goiter-inhibiting substance. In any case, our observations do not permit us to decide this point, inasmuch as the etiology of common goiter remains uncertain, besides being endemic in regions where there is no coreotrypanosis.

The predominant disease of the whole São Francisco river valley is malaria. It does not, however, offer anything of special interest and belongs mostly to benign forms; the transmission of most cases must be due to the ubiquitous Cellia argyrotarsis. The more severe forms are rare, and doubts may well be entertained as to the nature of some sporadic cases of malignant forms that were brought to our notice. Yellow fever is generally unknown in the region, but the occurrence of isolated cases cannot be entirely precluded, the more so as Stegomyia is highly disseminated and often breeds in the steamers on the river, as we had occasion to see for ourselves on board the “Presidente Dantas,” on which we traveled. It would also be easy for typhoid fever to occur but we did not hear of any authentic cases.

Nothing was heard of fevers with the characteristics of Malta Fever or of Pappatacci Fever. During the whole journey, we saw only one Phlebotomus, a male of P. intermedius, and Dr. Chagas saw a few specimens of an undetermined species at Pirapora.

We saw no Leishmaniosis in the zone traversed by us. Ankylostomiasis is less abundant than in other less arid zones. We did not find any cases of Bilharziosis and only a few of Elephantiasis, probably due to filariosis.

Some Dermatomycoses were observed but no cases of Blastomycosis, Sporotrichosis or Pemphigus foliaceus, nor did we see any Mal de Engasgo (Dysphagia); Alastrim (milk pox) was known in many places but the epidemics were already over.

A large number of cases of syphilis were encountered, some with very extensive lesions due to lack of treatment. We did not have the impression of greater malignancy than usual, such as is sometimes attributed to cases from the São Francisco River. Of yaws we saw only one case, which was confirmed by microscopic diagnosis.

If the large number of patients examined by us, in a region where medical treatment if often unavailable, is taken into account, one cannot say that any outstanding cases were found. We saw one osteosarcoma of the femur, some abdominal tumors, fibromata and ovarian cysts.

The use of river water for drinking is deplorable both from the aesthetic and hygienic points of view. Until now, it has not been possible to stop this practice, because other water is either entirely lacking or, when available, often not good and generally more or less brackish. Up to now, the river does not seem to have caused great havoc, even though it is used as a sewer as well as for stilling the thirst, but it does constitute a constant menace, especially in regard to Cholera, which might easily be introduced with the increase of traffic.

In regard to diseases of cattle, we saw only a few cases of peste de cadeiras (equine trypanosomiasis), which is well known in a certain region where there are capybaras and horseflies. The diagnosis was confirmed by inoculation of blood from diseased animals, which produced trypanosomiasis in the inoculated animals. There is also dourine and some other rather common diseases, but we did not find anything new or hitherto unseen by us.

The absence of interesting material for the study of pathology led us to hasten our journey somewhat and to visit several tributaries in the hope of finding better material. This hope remained unfulfilled and the few doctors we met during the second part of the journey did not furnish us with data on the occurrence of less common diseases.

Below Pirapora, the São Francisco River crosses an alluvial plain in which there are numerous “lagoas” (lagoons), some of which dry out as the dry season advances, whereas others merely become considerably reduced.

On both sides of the plain, there are many “serras” which approach the river at some points. They are generally not more than a few hundred meters high and their shape only rarely corresponds to that of usual mountain chains; generally, they are more mesa-like, especially when seen from afar. Sometimes they are covered by “capoeira” (scrub), occasionally becoming woods, but as a rule the vegetation is herbaceous and, in the arid places, xerophytic plants such as Cactaceae and Bromeliaceae are dominant. Often the rock surface is exposed, generally in very picturesque shapes; as it is mostly calcareous, there are a number of large and small caves; some of them were dry, others still contained some water. In other places, principally in riverbeds, where falls and cascades occur, sandstone rocks with the structure of schists take the shape of steps and terraces formed of large blocks. There are often cliffs or walls, more or less stratified and corroded, sometimes forming handsome pillars. They are steep but nevertheless invaded by plants, “gameleiras,” (Ficus), and “barrigudas,” i.e., bulging Bombax, which sprout in the interstices and send out long and tortuous roots (see fig.1, p.174).

In ordinary seasons, the riverbed is closed in on both sides by steep banks, which are higher or lower depending on the localities and especially on the water level. The current is generally slow. Despite its great width, which frequently exceeds half a kilometer, the river is not beautiful because the water is always turbid and the steep banks are generally formed of clayey earth. The vegetation of the high banks is mostly low and unattractive. The tributaries are often prettier and their water more limpid, or green, as sometimes indicated by their very names. They generally flow more swiftly, but this does not prevent navigation on many long stretches.

In the lower part of the river, clay is more or less substituted by sand, which also forms banks and dunes. The river often contains large islands. The water seems less turbid and the landscape becomes more interesting. The appearance of dunes denotes a zone of almost constant wind, which decreases the heat characteristic of the dry season. In this zone, navigation, which offers no obstacles at Pirapora, becomes more difficult and requires greater care. The rapid sinking of the level of the water, due to the advancing dry season, leads to frequent running aground on shoals. There are also a number of more or less exposed boulders in the riverbed. Slightly above Juazeiro, the riverboats have to stop during the dry season because of rapids, where, despite some dredging undertaken recently, the navigation channel remains shallow and narrow.

All the boats that are used have a shallow draught. They seldom anchor during the night when navigation is stopped. Mostly they are tied to the banks. In the absence of trees, strong poles are used, which are driven into the banks after being used by the sailors to vault ashore. One or two are enough to hold the boat. In the daytime, there are also many stops because the boats use wood for fuel, buying it along the banks, and they cannot keep going long without laying in new supplies. The wood is piled along the banks and thrown on board by hand, piece by piece, and is counted at the same time. Passengers go on board and ashore in a very primitive manner along narrow planks that are very insecure for shod feet (see figs. 2-5, p.175-78).

Even in periods of drought, the river carries a very large volume of water and this increases in a fabulous manner during floods. Notwithstanding the high banks, the river and its tributaries overflow everywhere and cover large stretches of land. In certain years, the flood exceeds all bounds and invades the riverside settlements, doing great damage. Besides trustworthy information given us in many places, photographs were shown which gave accurate views of the levels attained. During such periods, the riverboats navigate outside the bed for many miles, making use of temporary communication to shorten the laps.

A large number of lagoons fed by floods are found along the whole course of the river, so that it is difficult to find a small village that does not have one or more in its immediate vicinity. This explains the presence of “malarial fevers,” because these lagoons are the breeding ground of marsh mosquitoes, especially those of the genus Cellia, which are transmitters, chief among them Cellia argyrotarsis. A radical transformation of these circumstances is very difficult at present and only palliative measures can be resorted to.

As the dry season advances, most of the lagoons lose their water. Even before they become quite dry, mosquito larvae may vanish from those that receive no shade, owing to the powerful sunshine they are exposed to; we had occasion to observe this several times. The adult mosquitoes only disappear from shores of the lagoons much later and with them go the primary infections. But as there are many relapses, the disease itself does not die out.

These lagoons also help feed the human population as they are the principal breeding ground of many fish and are often visited by large numbers of water birds.

In spite of many villages and some fair-sized towns, the valley of the São Francisco River conveys the impression of a poor and backward region. The population shows hardly a trace of Indian blood. The Negro race, on the contrary, contributes very largely to its make-up, and the places where there are no entirely-white people are not rare. This of course influences the character of the population, which, on the whole, lives in a rather primitive manner. Comparison with settlements of the same size in other states of Brazil or in other countries does not favor the inhabitants of the São Francisco valley; this cannot be attributed solely to the lack of resources, because if, on the one hand, little is earned, on the other, little is spent. It is a fact that in these zones many of the necessities of life elsewhere become almost superfluous luxuries, but this should not extend to the need for hygiene. Nor can there be any progress as long as people are content to vegetate without trying to improve their conditions of life.

Besides the racial question, there are other factors that hinder progress. The hot climate, with mean temperatures very much above those found in the federal capital, and certain diseases, such as malaria, and to a lesser extent, coreotrypanosis and ankylostomiasis, tend to increase the indolence of a people who have no better examples set before them. The products of the earth exceed local needs only slightly and most of the products give unfavorable returns because of the distance from outside markets.

During our voyage, we found a few places, especially on the tributaries, where there were some signs of human effort, in wellcared-for plantations and gardens, but the proportion was small. The Corrente River is the only one where artificial irrigation is used on larger scale and with very good results. Elsewhere, often only a few meters from and above the river, the earth is arid and sterile and the sparse vegetation is composed of useless plants such as Ipomoea fistulosa and ruderal species which constitute the so-called “mato,” i.e., weeds, found at the edges of paths. On the lower São Francisco, windmills ought to work profitably as there is an almost constant wind; in times of need, few places should be more suitable for the use of sun-motors; both systems would make irrigation easier. It is to be hoped that, in time, conditions will improve and that this zone may come to justify the epithet of “extremely fertile,” which it certainly does not deserve at present.

Another factor which prevents progress is the great distance from the coast, so that even the less remote places are about one day's journey by railway. Navigation on the river is slow, and the distances are enormous and many products would not pay for their transport. Exports form the São Francisco River correspond to the three natural groups, agriculture, cattle-raising and minerals. Products not entirely consumed locally include brown-sugar loaves and spirits, which are marketed elsewhere in the same state. A little coffee travels down the river but it comes from fairly distant zones. Rice, which might well be produced on a large scale, is not grown at that rate.

Cattle raising by primitive methods furnishes a great many hides which are generally not tanned but form a large part of the cargo of river-steamers and give off a rather unpleasant odor. “Carne de sol” (jerked beef), dried in the sun, is much better than the usual salted meat imported from the south elsewhere in Brazil.

As the journeys are long, live animals are rarely transported. All the same, we met a cargo of mares traveling on a big barge towed by a motorboat. They had started from Pirapora and made the whole journey to Juazeiro.

Among natural products, the foremost are rubbers: “maniçoba” (Manihot glaziovii Muell. Arg.) and “mangabeira” (Hancornia speciosa M.). Many people gather rubber but that obtained from the “maniçoba” is of poor quality and very impure, so that at current prices it can hardly give a profit. There are few “maniçoba” plantations, which might easily be developed if it were worthwhile.

Another natural product is carnauba wax, which is used for gramophone records. Extraction seems profitable where there are large groves of this pal-tree. Some bees-wax is also produced.

Jatobá-resin, derived from Hymenaea courbaril L., is also a natural resource that might easily be produced on a large scale, but there does not appear to be much demand for it.

In every large village, hides and pelts of game are to be had but they are so poor that they are hardly more valuable than any other hide of the same size.

At Villa-Nova we saw the sun-dried flesh of mocós, cavy-like rodents, (Keradon rupestris) for sale at a miserable price. Dried surubim from the São Francisco is also sold in the state of Bahia. This fish, Pseudoplatystoma corruscans, might be exported farther if it were tinned, as it is excellent and could rival any of the imported kinds. The public authorities ought to study this possibility and try to help develop a new industry.

Of minerals traveling down the São Francisco, we saw only carbonados, i.e., the black diamonds, which come from a rather distant zone. They fetch higher prices than other diamonds of the same size, but total production is small. Salt was formerly extracted all along this zone but extraction seems to have ceased.

The idea of making money from minerals is very popular in this part of Brazil; we were given a number of specimens but they were all apparently devoid of intrinsic value and were only of interest because of the distant places from which they had been brought. The valley of the river itself does not seem to be blessed with mineral riches.

The fauna of the valley of the São Francisco is indicative of the lack of forest and of rain during all seasons. Many species of game that are dependent on wooded cover are absent, and the forms present are poor in individuals, owing to the ease of pursuit in country that does not provide adequate hiding-places. Some of the tributaries offer better conditions, but, generally speaking, the regional fauna is poor in larger animals. On the other hand, it comprises a few species which are not found at the latitude of the federal district. Thus we saw a different kind of “guariba” or howler monkey on the Grande River, whose banks contain large trees; i.e., Mycetes caraya Humboldt. The “anta” (Tapirus americanus) is absent from the more populous zones and even the capybara (Hydrochoerus capybara Erxl.) is generally not abundant and much shier than in other regions, where it is less persecuted. Of smaller rodents, the “mocó” (Kerodon rupestris), deserves mention; it lives in large numbers on the “serras” near the rivers, where it can hide more easily. They are very shy and seldom seen even in places where they are abundant. There are also two species of “cotia” or agouti, one of which (Dasyprocta agouchy) has a tail. Another small mammal characteristic of the lower São Francisco is the ball-armadillo, or “tatú-bola” (Tolypeutes conurus, Is. Geoff.), which is rather common in the region of Juazeiro. It can roll up into a ball, and seems to be the only species to thrive in captivity and even to become quite tame.

The only mammals we saw in freedom, during the journey, were a few “sagui” (marmosets), which are common near Pirapora; some bands of guariba-monkeys on the Grande River; the so-called wild dog at Barreiras and Poço de Mel, below Urubu; and mocós, bats and some rats and mice. A more accurate idea of the mammalian fauna is gained by seeing pelts, by examining the hides offered for sale and by obtaining information from competent and reliable persons. Among pelts, the spotted jaguar was often present and it is possibly still abundant in some of the “serras” near the São Francisco river, such as the Serra do Cabral, not far from Pirapora. The melanistic form seems rare. There are also some spotted wildcats. We saw only one pelt of the Brazilian “wolf” (Canis jubatus), which seems rather rare in this region. Ichthycion [sic] venaticus appears to be totally unknown. At Cidade da Barra we saw a very large skin of an “ariranha,” i.e., Lutra brasiliensis, the Brazilian otter.

We were shown some very tame “micos,” i.e., monkeys of the genus Cebus sp., on the Grande River; tame agoutis were rather common, but we were unable to get any live “mocós.” We got some skulls of the pampas-deer (Cariacus campestris Cuv.); the swamp-deer (Cariacus paludosus Desm.) is only found on the tributaries.

The avian fauna is richer. There are several species of small birds new to us, such as the scaled pigeon, or “fogo apagou” (the fire went

out), 1 Scardafella squamosa; the “sofré” [Xanthornus jamacai Gm.],

or jamacai oriole; the cardinal [Paroaria sp.], an oven-bird called “leather jacket,” etc. The “seriema,” i.e., southern screamer [Microdactylus cristatus L.], can often be told by its voice, and the emu (Rhea americana) occurs in some places. Among game birds, the spotted Nothura, or “codorna,” seems rather abundant and there are also Rufous tinamous and jacus, i.e., species of Nothura, Rhynchotus and Penelope on the banks of some rivers. The aquatic birds predominate and occur in large numbers owing to the favorable conditions found less on the river itself than in the large number of lagoons formed by it and its tributaries. The species observed will be mentioned in the diary. Here I shall just call attention to the fact that in some places, especially at Cidade da Barra, juvenile water birds, even of species which are seldom seen in captivity, may be obtained alive. Of the well-known ones, the red ibis, Endocimus rubber, is absent. In compensation, the Brazilian lapwing, or “téo-téo” (Vanellus cayennensis), is not absent anywhere.

As for reptiles, attention is first drawn to the “iguana” (Iguana tuberculata Laur.), which generally goes by the wrong name of “chameleon.” Although it is subject to constant persecution because of its edible and savory flesh, it still remains frequent. The other reptiles observed will be mentioned as occasion offers, but a few words may be added about turtles. The river, especially its lower course, would seem to offer excellent conditions for freshwater species, and yet there is not one valuable turtle either in the São Francisco or in its tributaries. The species we saw occasionally belongs to the genus Hydromedusa, which occurs everywhere but is not made much use of, though both the flesh and the eggs are edible. I cannot refrain from calling the attention of the authorities to the advantages of introducing the turtles of the Amazonas into the system of the São Francisco River, as might be done easily and at small expense.

Although there are many kinds of fish in the São Francisco, not more than a dozen species are used for food. These are, however, a very important resource for the regional population. The “surubim,” mentioned above, deserves to be singled out as it is a first-class fish as to flavor, because it has very few bones and also because it reaches an enormous size. The other species are mostly smaller and inferior in quality but are worthy of note as they are so very numerous. They will be mentioned again later.

Taking the number of species already present into account, it would not seem advisable to introduce other species and in any case this should only be done after very careful study of the problem. One experiment that might be tried without much risk would be the introduction of the manatee from the Amazonas, a herbivorous mammal adapted to aquatic life.

Of insects, besides the butterflies, or Lepidoptera, and Diptera, or flies and gnats, which will be dealt will be dealt with separately, both Ephemeridae, or dayflies, and Phryganeidae, a family of caddis-flies, were attracted to our lights and were present in few species but very numerous individuals. On certain occasions, large numbers of small Cycads also appeared. Two species of mole crickets (Gryllotalpa) were collected. As I had observed before on the Amazons, these crickets often live in the sand of rivers and can be found even on sand banks totally devoid of vegetation. Other insects that occur in sandy places, but during the larval stage, are the ant-lions (Ascalaphus and Myrmeleo), of which some very showy species were collected. In the same places, we also found Cicindelidae (tiger beetles), which came to the lights on rare occasion, and one Carabid beetle. A species of Dermestes deathwatch beetle, the larvae of which eat dead animals, occurs in large numbers on the dead “acary” (catfish) stranded on the beaches. As to the rest, beetles were almost entirely absent. The extreme rarity of insects during the dry season was already mentioned by St. Hilaire and one of us had noticed it in the Amazons as well. I would also like to mention a specimen of Mantispa caught on board by acetylene light.

The Crustaceans seen were all microscopic forms, cyclopoids and, in the lagoons, one Simocephalus and a Ceriodaphnia, which are the most common genera of Cladocera in Brazil.

On the same occasion, a species of Hydra was observed.

A large Scolopendra, or “lacraia,” and some scorpions, misnamed “lacráu,” were the most striking representatives of the Myriapods and Arachnids.

A certain number of Mollusks were also collected and are listed at the end of this report.

We also collected an interesting freshwater sponge, which might

belong to the genus Spongilla.2 It is rather frequent in some of the tributaries but we did not find it in the main river. The inhabitants are aware of its presence but know nothing of its nature.

A few words must be added about the regional Flora. Both the spontaneous and the cultivated plants comprise several forms which are either unknown or only rarely seen in Rio de Janeiro. In the “campos cerrados” formation, especially in the region of Pirapora, there occurs Magonia glabrata, known by the common name of “tingui,” which has large woody fruits, the contents of which are said to be useful both as soap and for killing fish. I must say that they seemed rather inert to us in both these roles. In the same zone, we also found “genipapo” (Genipa americana), “piquí” (Caryocar brasiliensis) and burity palms.

On the second part of the voyage, the carnauba palm (Copernicia cerifera Martius) and the coconut (Cocos nucifera) were observed. The salt contained in the soil seems to favor both these species and may explain why the latter fruits so well at such a great distance from the sea. In this zone we also found “umbuzeiros” or Spanish plum (Spondias tuberose) and “juazeiros” (Zizyphus joazeiro), neither of them in fruit.

Some plants which were introduced for cultivation have escaped and spread spontaneously; this applies especially to the Rose of Turkey (Parkinsonia aculeate L.) and to an arborescent Asclepiad (Oxytropis sp.), which is known as silk-cotton because of the fine silky cotton found in its large, apple-shaped fruits. Both are exotics, whereas Nicotiana glauca, an arborescent tobacco with very light-green leaves and yellow-green flowers, seems to be native. On the shores of the lower reaches there is a very abundant “areticum” with orange colored fruit; it is Annona spinescens, a wild relative of the cherimoya and sour sop. Various kinds of Cactus grow in the “serras.” The more or less arid campos formation to the sides of the rivers display pretty kinds of Evolvolus and Ipomoea, and on the banks there are many interesting species of Malvaceae, Sterculiaceae, Papilionaceae, Acanthaceae and Scrophulariaceae. Some of them are in cultivation and others deserve to be introduced into gardens, especially the different forms of Angelonia, Ruellia and Evolvolus. The lagoons sport many aquatic plants with lovely flowers. I tried to grow several of the plants of this region from seed, but succeeded only with Parkinsonia and Oxytropis. Both of them develop very slowly in Rio de Janeiro. Further details regarding the flora will be found in the diary of the journey, which follows.

 

Diary of Dr. LUTZ

April 17. I started from Rio yesterday and arrived tonight in Pirapora. The physical characteristics of the region were already evident during the last part of the journey. There are extensive “campos” (savannahs) with many stunted trees, so twisted that it would be difficult to find a straight stick among them. Magonia glabrata, common name “tingui,” is very abundant and exhibits large, ball-shaped fruits with three crests. On the horizon there are more or less distant “serras,” mostly fairly level on top. The railway follows the course of the Das Velhas River until Lassance but after that leaves it and cuts obliquely across the land, separating this river from the São Francisco. We passed at the foot of a small “serra” which seemed to have an interesting flora so far as could be judged from the train. After that came an extremely long straight stretch. The train arrived after dark and the town is far from the station, which at present is the end of the line (see figs.6-8, p.183-84).

April 18. As I have to wait for my traveling companions, I decided to take some excursions. I began, today, by accompanying Drs. Eurico Villela and Leocadio Chaves to Guaicuhy or Bom Successo at the confluence of the S. Francisco River and Das Velhas River. The latter is smaller but runs more swiftly. Both are very muddy and flow between high banks, topped by trees and shrubs that do not form real forest. We saw many aquatic birds, including lots of egrets, a band of Brazilian storks known as “jabiru-moleque” (Euxenura galeata), roseate spoon-bills, (Ajaia ajaja) and other, smaller species. On the banks of the São Francisco, which are about five meters high, there were many holes, which are the openings of the nests of the great-ringed kingfisher, Ceryle torquata; the birds were seen near them (see fig.9, p.185).

It is very hot, as it has not rained for many days and the earth is rather dry. Guaicuhy is small and seems to be in decline. There are about 150 houses, all of them small and badly built, offering good shelter to the wall-bugs or “barbeiros,” which transmit Chagas’ disease, and which are frequent here. All the same, there were a few signs of cultivation and we saw orange and lemon-trees, sugarcane and Genipa americana, besides white fig trees and piqui, the latter perhaps spontaneous.

There were many patients with Chagas’ disease and this prevented us from going farther. Some of them had heart symptoms and others symptoms of the central nervous system. There was also one case of incipient myxedema. Alterations of the thyroid are frequent but large goiters are comparatively rare (figs.10-11, p.186).

We returned to Pirapora the same day, traveling on board the “Presidente Dantas.” The captain, Mr. Arthur Vianna, is a pleasant companion and did much for us; so did Major Ramos, who went with us and who has kindly undertaken to look after our mail.

April 19. As I foresaw yesterday, but contrary to local predictions, the weather has become rainy. In the morning, a torrential downpour inundated the streets and part of the hotel. In the afternoon this unseasonable storm abated somewhat and allowed us to go out for a while. Our first trip was to the waterfall. I had visited last year; at that time the river was very low and allowed us to reach the main fall, which is quite picturesque. I then combined the visit with a bath, and on the stones just below the surface I collected a large quantity of a Podostemonacea of the genus Ligea; they were literally covered with larvae and pupae of a species of Simulium, or black-fly, which is peculiar to the falls and cascades of the larger rivers. I also observed that the adult emerges when the pupae become exposed to the air at low water.

This time the water was too deep for us to reach this place and the boulders were covered by a slimy and extremely slippery layer. At great cost we secured a few pupae of this species, which apparently is the only one found in this waterfall. Another podostemonaceous plant, which seems to be a Mourera, grows there but only from the middle to the far side and I could not find it this time. It is not made use of by the larvae and pupae of the black fly, Simulium orbitale Lutz, a species which does not seem to attack people but horses. Many small fish were trying to go up the falls.

The town of Pirapora, which we looked at afterwards, is quite large and seems to be going forward. If allowance is made for the great distance from the coast, one gains a rather favorable impression without finding it especially attractive. The best building of the zone is located on the other side of the river and is used as a School for Apprentice Sailors. The houses and even the churches are modest but the streets are wide and the sandy terrain offers many advantages. The falls are at the level of the town and the port, slightly below them. We saw several cases of coreotrypanosomiasis and of malaria, one of articular rheumatism and some commonplace diseases (see figs.12-13, p.187-88).

April 20. Through the kindness of a fellow lodger in the hotel, Mr. Mattoso, who is at work lengthening the railway and who knows the region well, we obtained horses for an excursion to Brejinho, on the “Serra” and “Fazenda” of the same name. We had to cross the river with the horses on an “ajoujo” (two boats tied together side by side) and took the occasion to visit the school for sailors, which is ready but not open as yet. On the excursion we saw several interesting plants, such as a Mimosa with showy red flowers and another decorative plant which here is called wild cotton, a name used elsewhere for quite different species. It is shrub which recalls a large Rhododendron in habit but the flesh-colored flowers are more like the European wild rose. I saw it on several of the “serras” in Pirapora but not farther away, and I felt sorry not to have taken herbarium specimens. It is probably a species of Kielmeyera. We photographed the falls, which run over huge boulders. I collected a few Simuliids and Tabanids. We also caught, alas quite unwillingly, a good supply of the diminutive ticks that are a terrible plague in this region. Luckily they became less common during our voyage and finally disappeared altogether (see figs.14-15, p.189).

April 21. I made an excursion to Burity das Mulatas, the second to the last station, on the railway line. In this place there is a stand of burity palms in the middle of a marsh and there Dr. Chagas had found Stetheomya nimba, an interesting species of anopheline. We failed to get another specimen even with the aid of a horse as bait; neither did we find the larvae, which probably do not live in bromeliads. In the marsh water there were those of Cellia, Uranotaenia and Culex cingulatus and also a species of Ceriodaphnia (Crust.). I caught some interesting horseflies, but on the whole our efforts were poorly rewarded, the more so as this place had yielded some interesting forms earlier. This was also the first positive proof that the good season was already over. We looked unsuccessfully for “barbeiros,” though this region is infested. Finally, we had a long wait for the train, which arrived four hours late, so that we only got back to Pirapora at 2 o'clock in the morning.

April 22. Today we received the bulk of our voluminous baggage and stowed it onboard. We saw more patients. I found Cellia albimana in the hotel. On the night-train, which luckily was not late, there came Dr. Astrogildo Machado to substitute Dr. Chagas on the journey. As everything was ready, we slept on the boat. The river has fallen very much in the last few days so it had to be moved to another mooring to avoid being left stranded.

April 23. Anchor was weighed early and at 8.30 a.m. we arrived in Guacuí, 20 kilometers from Pirapora. At 12:37 we started out on horseback for the Serra do Rompe-Dia, which is part of the Serra do Cabral. This used to be known as the hunting ground of jaguars, which are not quite extinct even now. During the rather steep climb we first found the twisted vegetation of the “campo cerrado,” or dense savannah; higher up we met with burity palms and an

extraordinarily large Eriocaulacea. 3 Then we rode through open savannah, which seemed fit for raising cattle but saw only a relatively small number of head; we also crossed several rivers, on the boulders of which I found the larvae of Simulium rubrithorax. After passing cliffs of reddish sandstone decomposed into fantastic shapes and descending through very thick scrub, we arrived at the mouth of a cave which we had been told about and which we wanted to visit. It consists of a tunnel excavated by the water of the brook “Rompe-Dia” and is about 30 meters long and open at both ends. The floor of the cave is formed by the rock itself, which makes any hopes of paleontological findings remote. Stalactites are barely present. This cave is very difficult to find and hardly worth the trouble of getting to, but the view from the “serra” opens onto a very interesting panorama. This range seems less arid than those that occur farther downstream and also seems to have a rather rich flora. We saw many lovely Leguminosae, trumpet vines, Acanthaceae, bind weeds, etc. We also saw the footprints of tapirs and peccaries. On the way back, I caught crepuscular Tabanids. Before getting to the “serra,” we had crossed a zone with many tall trees, among them Enterolobrium timbouva Mart., common name “timbaril.”

In Guaicuhy we found many Cellia argyrotarsis, the only anopheline which can be held responsible for the frequent malaria of this zone. Slightly inland from this place lies Porteira, a rather old and completely decadent settlement, probably on account of malaria; this is not surprising as it stands beside a lagoon that reaches from one village to the other and must be an excellent breeding place for Cellia, the more so as it is not very much exposed to sun-light.

A very long time has passed since the Das Velhas River was first settled and a large town should have developed here by now, were it not for malaria. There are two large unfinished churches, but they are even more dilapidated than the village (see fig.16, p.190).

April 24. Yesterday and today several patients were examined and some of them photographed. We saw an interesting case of generalized Eczema marginatum of Hebra, which denotes a hot climate.

The journey was continued in the morning and after a short lap, we arrived at the Fazenda Jatobá, but did not find the horses we had requested ahead. They arrived very late so that there was hardly time for the excursion we had planned to the falls of the river Jatobá. Nevertheless, we decided to start; we first crossed a low woods, then we arrived at a “serra” which was not high but very steep and covered, at first with thick and later with more open scrub. We finally got to the waterfall, which is rather voluminous and picturesque,

something like the Salto de Itu.4 We took photographs, and collected Simulium, the larvae and pupae in the river and the adults on the horses. I had the impression, however, that the real breeding places were not yet accessible. There were no Podostemonaceae either.

During the trip we were very much bothered by small flies of the genus Hippelates. We were overtaken by dusk and, as our guide lost his way, almost had to spend the night on the savannah. At one point we were assaulted by a large number of gnats, which bit without buzzing. We were unable to see if they were Cellia or Culicoides. We arrived well after nightfall at the fazenda Jatobá, where there were only a few quite primitive houses. This “fazenda” and the waterfall, which could furnish quite a lot of water-power, have recently been bought by the government of Minas Gerais (see figs.17-21, p.192-94).

April 25. We left early and arrived at 10 o'clock at Extrema de Montesclaros, 87 kilometers from Pirapora. It consists of about one hundred houses and it looks better than Guacuí. Here, exceptionally, they have some cisterns and wells, whereas in this region as a rule, only river-water is drunk. We were told that there were no Triatoma and no goiter. However, we did find both, as well as many cases of intermittent fever. We also saw and photographed a case of osteosarcoma of the femur.

The voyage was reassumed at 3 p.m. At dusk we passed the bar of the Paracatu, an important tributary, and stopped to spend the night between it and São Romão (see figs.22-28, p.194-99).

April 26. We arrived early at São Romão, which, according to information given us, comprises 500 to 600 houses. It is already one century old, but still quite primitive. The water of the river is drunk and the place seems rather unhealthy. We saw many patients with endemic diseases: goiter, trypanosomiasis and malaria. There was also one patient with a very large abscess of the liver, one case of ankylostomiasis and one of rather extensive tertiary syphilis. After taking some photographs, we went on to São Francisco, where we arrived at 4 p.m., in time to see a good many patients.

April 27. Together with several residents, we made an excursion to the Lagoa do Feijão. It is very large but about one league away from the town so that it does not affect the health of the inhabitants. On the other hand, Cellia argyrotarsis is very abundant in the town itself and immediately invaded our steamer. It has breeding places in or very near the settlement, which is subject to flooding. The biggest flood of recent years was that of 1906. To judge by the places pointed out to us as having been submerged, the river must have risen at least 10 meters above its lowest level. As a rule the difference between high and low water is 8 meters. This year's flood, which was rather high, has already gone down about 1 meter. It began in February and continued into March, inundating a large part of the town.

The church is rather large but not quite finished and occupies the highest site on the bank, a sort of rocky promontory.