(Chapter 18) Footnote 93:

Vesalius is being sarcastic: indubie ... nostri coccygis ... meminisset, “our coccyx” being a human as opposed to canine or simian configuration. Such an index of bones is not part of the ancient text as transmitted, and would be an anachronism in an ancient MS. Vesalius may be suggesting (still sarcastically) that we consult an index of bones at the end of the 1543 Greek edition by Martin Grégoire and Jacobus Sylvius (see n. 60 above). Vesalius’ point is that the coccyx described by Galen is not a human coccyx. His discussion here refers obliquely to Galen’s statement at the end of De ossibus that “this is all beginners need know about bones and the construction of the skeleton, and that there is no need to discuss now any small bone found in other parts, as in the heart, larynx, and nose, and in some of the digits which are called sesamoids, or anything else of the kind.” (2.777.15-778.3, tr. Singer 1952 p. 775)