Al-Jahiz lived in a transitional time when it came to textual transmission. Scholars were just beginning to author books and transmit them intact, rather than compiling information and transmitting that information in such a way that it could be recompiled and reordered by the recipients. This is probably the reason why his longest work, the seven-volume Book of Animals, is so cryptically organized. There are chapter headings, but they do not necessarily correspond with the contents, or with the major textual divisions, and there are various ways to understand how the text is organized. Many modern critics have simply labelled it a digressive text. In this talk, I will turn to the manuscripts, asking how the copyists, commentators, and readers seem to have interpreted the organizational structure of this mysterious text. The results show a variety of approaches, and also reveal some differences of opinion about whether to treat the text as a biological work or a lexicographical one.