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Show 396 PROF. HUXLEY ON THE REPRESENTATIVES OF [May 27, Giinther'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 opportunity, 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 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 (Bg) detached from its origin. E 0. Exoccipital. Qu, Quadrate. M. Mandible. Hy1, Hy2. Anterior and posterior cornua of the hyoid. Sth. "Stylo-hyal" part ot the anterior cornu. E St. Extrastapedial cartilage. Ph. The membranous wall of the pharynx, attached, in fronl, to the hyoidean cornua, and then continued into the aponeurotic outer wall of the tympanic cavity, ty. |