OF REPTILES AND BIRDS. 13 



A transverse section (fig. 12) throngli the tongue of Ameiva a short distance behind the 

 fork, closely resembles a section from the corresponding part of the ophidian tongue 

 (fig. 8). The upper part of the tongue is expanded, and separated from the lower part 

 by a longitudinal furrow. The verticalis forms a median partition, and its fibres spread 

 out fan-like above, intermingling with those of the transversi and forming septa which 

 divide up the lingualis, which lies directly underneath the dorsal skin. The divisions of 

 the lingualis are smaller and more numerous in Ameiva than in Ancistrodon. The trans- 

 versi inferiores extend from the lower end of the verticalis along the lower surface and 

 the sides of the tongue, around the ceratoglossi, and also spread out fan-like above. The 

 transversalis superior extends across the tongue above the ceratoglossi, but is not very 

 distinct, being closely interwoven with the fibres of the verticalis and transversi inferiores. 

 The ceratoglossi are large, and occupy the lower part of the tongue, and in Ameiva are 

 gathered into distinct bundles, which is not the case in Ancistrodon. The nerves in 

 fig. 12 are drawn black. The hypoglossus lies in the midst of the ceratoglossal muscles. 

 The lingualis lies just above and outside of the same muscle, and underneath the 

 M. transversi. It is already divided into two branches, one, the superior, considerably the 

 largest; both branches are surrounded by connective tissue. In the snake, fig. 8, the 

 lingual nerve is separated from the ceratoglossal muscle by a layer of fibres belonging to 

 the transversus superior, but in Ameiva this layer is wanting, and the nerve and the 

 connective tissue accompanying it lie, not in the midst of, but entirely below the superior 

 transverse muscle. The epithelium is most developed on the upper surface, whichs is 

 scale bearing in Ameiva. All the muscles are enclosed in a common sheath, but the limit- 

 ation of the muscular core is less conspicuous than in the snake, there being less 

 adenoid tissue separating it from the epithelium. 



III. Tongue of the Chamaeleon". 



The peculiarities of the Chamaleon's tongue are so great that I was particularly 

 desirous of examining it, and through the kindness of Mr. S. W. Garman I obtained a 

 tongue of 0. dilepis. My hope of being able to homologize the muscles with those of 

 the moccasin and the Ameiva, has unfortunately been annulled by unexpected compli- 

 cations of the disposition of the fibres. The chamaeleon's tongue has been the subject of 

 several investigations. The amusing speculations of the French Academicians reported 

 by the famous Perrault (xiii) were followed after a long interval by the more valuable 

 researches of Duvernoy and Houston (xi.) 



Duvernoy's observations and conclusions appear to me the most accurate and valuable, 

 and remarkably trustworthy. The memoir of Mivart (xii) must also be mentioned, as it 

 contains a description of the muscles of the hyoidean apparatus. 



I give a figure, fig. 2, and description of the general form of the chamaeleon's tongue, 

 to spare the necessity of consulting Duvernoy, (v and vi). The tongue is cylindrical 

 with the tip enlarged, and has three distinct divisions : 1, basal, only partly represented 

 in the figure, with transverse folds ; 2, middle, with a smooth surface ; both these parts 

 are extensile ; 3, the bulky tip, glandular and not extensile ; called la massue, by Du- 

 vernoy. A cylindrical extension of the hyoidean apparatus traverses the two extensile 



