1S87.] IN THE LARYNX OF THE ANUROUS AMPHIBIA. 499 



thinner and more vibratile than the rest, a beautiful parallel striation ; 

 the epiglottis is also membrauoua, hut supported upon a connective- 

 tissue framework, which is densest along the lines of development 

 of its paired outgrowths. Neither epiglottis nor epilaryngeal folds 

 appear to have given attachment to definite muscles ; the epiglottis 

 was very flexible in life ; and although unable to trace a direct 

 muscular connection, I incline to the beUef that it was under mus- 

 cular control. 



What may be the precise function performed by these interesting 

 structures, I do not pretend to say, but I hold it indubitable that 

 they are concerned in phonation. If this be admitted, a most inter- 

 esting parallelism becomes obvious between the higher Amniota 

 (Mammalia) and the higher Ichthyopsida (Anura) with respect to 

 the appearance of the epiglottis as an accompaniment of specialized 

 laryngeal activity ; and we have good reason for believing that organ 

 to have been primarily connected with phonation — a deduction 

 which all recent investigation into the function of the Mammalian 

 epiglottis upholds. 



While the epiglottis makes its appearance in the Amphibia as an 

 accessory voice-organ, its development does not appear to be of 

 necessity related to a high development of the vocal sac. Heron 

 Royer has lately described * the larynx of Hyla meridionalis {bary- 

 tonus, Royer) ; in it, in spite of the immense development of the gular 

 sac, there does not appear to be anything present of the nature 

 described above. Royer has further pointed to specific differences 

 between the larynges of H. arborea and H. meridionalis ; Mr. Bou- 

 lenger, however, informs me that he has found the same to be of no 

 specific value, and I fully share that belief. 



Thanks to Prof. Huxley and Mr. Boulenger, I have been able to 

 examine a series of specimens, with the result set forth in the 

 following table ^: — 



a. Epiglottis present : epilaryngeal folds confluent behind. 



Heleioporus albopunctatus. S . 

 Leptodactylus pentadactylus, 



6 . 



Calyptocephalus gayi. <S . 

 Ceratophrys americana. S • 

 Chiroleptes australis. Adult (S . 



b. Epiglottis present ; epilaryngeal folds not confluent behind. 



Hyla ccerulea. cS . 



* dolichopsis. S > 2 • (^ 



second c? showed no traces.) 



Hyla lichenata. $ . 

 *Mana pipiens. d > ? 



c. Epiglottis present, but small ; epilaryngeal folds absent. 



*Rana esculenta. c? , ? . 

 * temporaria. d , 2 



*Bombinator bombimis. S . 

 Chiroleptes alboyuttatus. S . 

 australis. 6 juv. 



' "Note sur une forme de Eainette nouvelle pour la fauna fran9ai8e," Bullet. 

 See. Zool. d. France, vol. ix. 1884. 



* One specimen only examined, excepting those marked *. 



