together. It extended the whole length of the chest (Fig. 6, v.) 

 fron\ the superior aperture to the liver, and was not less when dis- 

 tended than two lines in diameter. Both were filled with coagu- 

 lated blood ; and the texture of their coats appeared the same as 

 that of the veins which emptied into them. Their use may proba- 

 bly be connected with the varying condition of the circulation in 

 the skin and the erectile portion of the tongue, on which I conceive 

 depend all the phenomena for which these two parts have gained 

 such notoriety. They may serve as reservoirs for the blood, when 

 suddenly abstracted from either of them, previous to its readmission 

 into the heart. 



After this detailed description of the structure of the chameleon's 

 tongue, we may be enabled to estimate the applicability of the se- 

 veral theories, which have from time to time been advanced, to 

 account for its peculiar powers of motion. 



It was denied by Marmol, who examined many chameleons for 

 the purpose of clearing up this point, that their tongue had any such 

 powers at all. He assures us that it is never exercised as a trap for 

 insects, and that any thing wiiich he had observed of the animal 

 would not induce him to change his opinion, that air and the sun's 

 rays are its only nutriment.* 



M. Perrault attributed the elongation to an expiratory effort of the 

 animal which darted its tongue from its mouth, " comme si il la 

 crachoit avec violence."-f- The great size of the lung lie supposed 

 was for the purpose of effecting this movement. But there is no 

 circumstance connected with the anatomy of the organ, or its mode 

 of advancement, to countenance this explanation. Besides, the 

 chest during the act, in place of evincing the motions attendant on 



* See Mem. de I'Acad. Roy. des Scienc. T. 3. Ire. partie, p. 47- 

 t Ibid. T. 9, page 156. 



