- Pleurodont; tongue very short and scaly; no osteoderms; supratemporal fossa roofed over by the cranial bones; eyes devoid of movable lids; tympanum exposed; femoral pores present; limbs and tail well developed.
The chief artistic features of the church are the group of the Last Judgment sculptured on the tympanum above the west door, and the painting by Ingres representing the martyrdom of St Symphorien, which took place at Autun in 179.
Although the present article does not discuss mammalian osteology in general (for which see Vertebrata), it is interesting to notice in this connexion that the primitive condition of the mammalian tympanum apparently consisted merely of a small and incomplete bony ring, with, at most, an imperfect ventral wall to the tympanic cavity, and that a close approximation to this original condition still persists in the monotremes, especially Ornithorhynchus.
The tympanum itself has been regarded as representing one of the elements - probably the supra-angular - of the compound reptilian lower jaw.
C. 1540), a native of Dijon, and pupil of Leonardo da Vinci, but the sculpture of the portals, including "The Last Judgment" on the tympanum of the main portal, is probably from his hand.