394 PROF. HUXLEY ON THE REPRESENTATIVES OF [May 27, 
lage (S.S¢). The inner surface of the posterior edge of the supra- 
stapedial cartilage is thus closely connected with the posterior part 
of the parotic process of the skull, while its anterior end comes into 
contact with the quadrate bone, which is connected with the front 
part of the same process. 
Fig. 1. 
S.S¢ 
Art 
Side view of the right side of the hinder part of the skull of a young Crocodilus 
biporcatus. The squamosal, the postfrontal, and the tympanic membrane 
are removed, and the quadrate (@z) is, in part, indicated only by an 
outline. 
E.O. Exoccipital. Pc.c. Cartilaginous termination of the parotie process of the 
skull. £.S¢. Extrastapedial process of the stapes. S.S¢. Its suprastapedial 
process. Sth. The stylo-hyal cartilage supposed to be seen through the 
quadrate bone. a, , Air-chambers of the quadrate. D.p. Pneumatic duct, 
leading from the posterior of these (q) to ¢, the air-chamber of the articulare 
(Art). Mck. Meckel’s cartilage. 
In the natural position of the parts, and when the head is hori- 
zontal (fig. 1), the plane of the extrastapedial cartilage is also nearly 
horizontal. The long axis of the suprastapedial cartilage is inclined 
at an angle of 45° to that of the extrastapedial cartilage; and the 
posterior ends of the two cartilages approach one another very 
closely. In close proximity to both lies the upper and broader end 
of a small and short rod of cartilage (Sth) which tapers below to 
a free rounded extremity. It lies upon the upper and posterior face of 
the quadrate bone ; and its lower extremity terminates some distance 
_above the upper end of the pneumatic duct (D.p), the fibrous wall of 
