of the Tongue of the Chameleon. 169 



stance is noticed by them only to excite our astonishment, " que Aristote ait 

 dit que la chameleon n'a du sang q'autour t!u coeur, et des yeux, et que la 

 plus part des modernes le mettent au rang des animaux qui ont peu de 

 sang." " 



The lingual arteries, which are derived from the carotids, are of considerable 

 magnitude (Fig. 2, 6, z.) They run before the posterior cornua of the os- 

 hyoides as single trunks, and are soon subdivided into numerous small 

 branches, which ramify through the erectile portion. Coagula of blood, toge- 

 ther with the tortuosity of the vessels, prevented the ingress of injection to 

 their minute terminations, though it passed sufficiently far to show their ge- 

 neral course and distribution. 



Two large veins (Fig. 5, 6, x.), which take their origin round about the 

 prehensile and erectile portions of the tongue, run along its lower surface, 

 and having arrived at the os hyoides, where they are very conspicuous, one 

 passes on either side of the root of the style, between it and the hyo-glossus 

 muscle; then it escapes between the anterior and posterior cornua, and ap- 

 plies itself on the side of the trachea (L). It next courses along the trachea, 

 first overlapped by the thyroid gland (r), then by the carotid artery (y), and 

 aorta (u), and at length opens into a large sinus (v), connecting with the cor- 

 responding auricle of the heart (t), by an orifice which is distinct fi-om that of 

 the jugular vein, and a little to its inner side. I have succeeded in injecting 

 the lingual veins with quicksilver through a pipe introduced where they lie 

 on the trachea, and, when distended with this fluid, they acquired a size fully 

 equal to that given them in the plate. The quicksilver ran into the tongue, 

 and filling many of the larger branches, produced an evident turgescence in 

 the most dependent part of the organ ; but the delicate vessels being unable 

 to support the increasing weight of fluid, it soon becomes extravasated : suf- 

 ficient, however, remained to show in a preparation the extremely vascular 

 nature of the organ. I am happy in being also able to adduce, in evidence of 

 the fact, the names of Professors Jacob and Harrison, who witnessed the re- 

 cent injection of the vessels, and who can bear testimony to their magnitude 

 and numbers. 



The exact mode of termination of the ultimate vessels in the tongue maj' 

 not be easily ascertained ; but, from the extremely fine ramifications which are 

 perceptible in it, I am inclined to think that it is by a congeries of vessels, the 

 termination of arteries and commencement of veins, without the intervention 

 of a spongy or cavernous texture f. And, if this were established, it would, 

 in my opinion, afford a still farther confirmation of the analogy between the 

 erectile portion of the chameleon's tongue and the corpus cavernosum, for that 

 the latter is purely a vascular body, without any intermediate cells between 

 its arteries and veins, many experiments and observations have satisfied me. 



The heart in the chameleon consists of one ventricle (Fig. 6, s.) and two 

 auricles (t, t), with each of which is connected a large sinus (v), for receiving 



• See Mem. de I'Acadeniie Royale des Sciences, T. Sine, Ire partie, p. 4<). 

 t 'I'he minuteness of tlie globules of the blood in this animal, which renders it hi)jhly dif- 

 fusible, appears particularly favourable for making observations on the magiiitude of its ultimate 

 vessels ; for, with a gla.ss, one could discover vessels tinged with the coloured parts of the blood, 

 which were not visible to the naked eye. 



