(Chapter 38) Footnote 6:

Disproportionately and inaccurately illustrated in figures 12 and 13; more accurately proportioned (but more canine in its general aspect) in figure 2. Figures 1 and 3-11 are human cartilages, although there are some inaccuracies in the drawings. In De re anatomica (1559, p. 43), Vesalius’ former colleague Realdo Colombo would write that Vesalius “used always to dissect not a human larynx but that of an animal, and in public dissection theaters at that, quite frequently when I was present.” The reason may be found in Baldasar Heseler’s account of Vesalius’ first public anatomy at Bologna in 1540: “D. Vesalius brought us the larynx of an ox and some other animals, and out of the larynx of the ox he had cut the various parts. Because, he said, in the hanged subjects we cannot see the larynxes, for they are destroyed by the noose; but they are however quite different [in man and in animals], as you will hear.” (tr. Erikson 1959, p. 285).