The accurate knowledge which Aristotle exhibits of the anatomy and habits of marine animals, such as the cephalopoda and the larger Crustacea, leaves no doubt that he derived it from actual observation.
"Fathers of Biology"
Charles McRae
Professor Owen says, "Respecting the living habits of the cephalopoda, Aristotle is more rich in detail than any other zoological author."
"Fathers of Biology"
Charles McRae
The cephalopoda are abundant, among which 40 species of Ammonites are now known, 10 being peculiar to this subdivision, and the rest common to the beds immediately above or below.
"The Student's Elements of Geology"
Sir Charles Lyell