Doctor Dolittle and the Secret Lake

Doctor Dolittle and the Secret Lake was published in 1948, one year after Lofting's death, and is one of the two posthumous books in the series. The novel had been mostly drafted by Lofting before his death and was edited into final form by his widow. The plot takes the doctor and his animals on a long expedition to Africa to find a legendary tortoise named Mudface who supposedly survived Noah's Flood. The book accordingly contains a lengthy embedded narration in which Mudface describes what he saw of the Flood from the inside.

The pre-history sequence is unusual in the series and reads almost like a Lofting variation on a Genesis legend, with extended scenes of antediluvian life, the actual Flood, and Mudface's slow journey to safety afterwards. The frame story includes the standard expedition material with crocodiles, secret lakes in central Africa, and the doctor's animals doing their characteristic things. Posthumous editing makes the prose slightly uneven, but the Mudface story alone justifies the book.