396 PROF. HUXLEY ON THE REPRESENTATIVES OF [May 27, 
Ginther’s statement (Phil. Trans. 1867, p. 620), that, in this Lizard, 
the stapes is ‘‘attached by a fibro-cartilaginous ligament’’ to the 
anterior cornu of the hyoid, strongly attracted my attention when I 
read his valuable memoir on this reptile; and having had an oppor- 
tunity, thanks to him, of examining into the question for myself, I 
can fully confirm his assertion. 
Nothing can be more instructive than the arrangements represented 
in Fig. 3. Sphenodon has no externally visible tympanic membrane ; 
but on removing the integument which lies over the aural region and 
the anterior portion of the digastric muscle, the fibres of a strong 
aponeurotic expansion, which takes its place, are seen to pass from 
the posterior edge of the quadrate bone and from the angle of the 
Fig. 3. 
Dg 
The right side of the posterior half of the skull of Sphenodon punctatum, twice 
the size of nature. 
The integument is taken away and the digastric muscle (Dg) detached from its 
origin. EO. Exoccipital. Qu. Quadrate. I. Mandible. Ay}, Hy’. 
Anterior and posterior cornua of the hyoid. Sth, “‘Stylo-hyal” part of 
the anterior cornu. # St, Extrastapedial cartilage. Ph. The membra- 
nous wall of the pharynx, attached, in front, to the hyoidean cornua, and 
then continued into the aponeurotic outer wall of the tympanic cavity, ty. 
