196 



on the end is again deepened by the action of the retractor muscles, 

 and the relaxation of the mucous membrane on the sides ; and the 

 hyo-glossi draw in the tongue, folding up the erectile portion and 

 replacing the prehensile on the style. The parts thus arranged, the 

 organ is made fit for the ordinary purposes of mastication by the 

 annular muscle fixing the prehensile portion, and preventing its 

 rotation on the slippery style, and by the hyo-glossi drawing it in 

 the direction of the cornua of the os hyoides, so as to obviate any 

 displacement forwards. 



The chief objection urged against this theory is the difficulty of 

 conceiving how vascular congestion could effect the elongation with 

 the rapidity ascribed to it during health. This objection, however, 

 does not apply to the act as observed in those animals from which I 

 have drawn my conclusions, for the motion of their tongues was by 

 no means so rapid as to be irreconcileable with such a cause. It 

 was not more rapid than the instantaneous blush on the cheek of 

 youtli ; nor more rapid than several other phenomena which are 

 universally allowed to be the result of vascular turgcscence. How 

 far in a state of nature the rapidity of projection exceeds what was 

 observed in those weakened by confinement, I cannot determine ; 

 but perhaps the difference may not be so great as is usually believed. 

 Few of our accounts on the subject have been given by naturalists 

 on the testimony of their own observation ; and it is not going too 

 far to suppose, that it may have been with their descriptions of the 

 chameleon's tongue, as with those given by them of its skin, in 

 which fancy contributed so largely to the colouring : for we must 

 admit, that much of imagination has mingled with their accounts of 

 the organ, when we find it described, and even figured, as in the act 

 of turning backwards and seizing objects placed on its tail, a range 



