(Chapter ad) Footnote 6:

Os frontale (1); os parietale (2); os occipitale (1); os sphenoidale (1); os temporale (2); os ethmoidale, lamina cribrosa (1, Vesalius’ 8th bone of the head). The 1555 edition describes the skull differently: “as it occurs in cemeteries, or is commonly represented otherwise.”