556 REPTILIA. 



useful to them than to the fishes described in the last chapter ; 

 and we are, therefore, not at all surprised to find the tongue in 

 almost every family appropriated to a totally different use, and not 

 unfrequently converted into an apparatus of prehension, whereby 

 the food is seized and conveyed into the mouth. 



In the Batracoid Amphibia, for instance, we have a remarkable 

 example of this provision. The Frog and the Toad, notwith- 

 standing their slow and clumsy movements, are destined to feed 

 upon insects, and consequently must be provided with some instru- 

 ment by which such active prey may be caught. The organ pro- 

 vided for this purpose is the tongue, which, by a slight modifica- 

 tion in its structure, becomes changed into a prehensile forceps, 

 admirably adapted to such an office. The tongue of the Frog, 

 instead of presenting the usual arrangement, is found to be fixed 

 to the symphysis of the lower jaw, and folded back upon itself, so 

 that its point, which is free and bifid, is lodged in the throat. 

 Thus provided, the Frog is enabled to seize its victim with the 

 greatest ease. No sooner does a fly approach sufficiently near than 

 this living forceps is rapidly everted ; and the insect, being seized 

 by its furcate extremity, is as speedily brought between the jaws of 

 its destroyer. The teeth of the Batrachia very much resemble those 

 of the generality of fishes ; being simple points soldered to the sur- 

 face of the jaws, but not implanted in sockets, sufficient to give a 

 secure hold of their food, but quite unadapted to mastication. 



(612.) The Cameleon is another curious example of a reptile 

 obliged to employ its tongue in securing insect prey. The Came- 

 leon is arboreal in its habits : its feet, cleft, as it were, into two por- 

 tions, firmly grasp the boughs upon which it climbs ; while its well- 

 known power of changing the colour of its skin, so as to imitate 

 that of the branches around it, efficiently conceals it from obser- 

 vation. The tongue of this creature, when extended, is as long as 

 its whole body, and is terminated by a club-shaped extremity, 

 smeared over with a viscid secretion : when an insect comes within 

 a distance of five or six inches from the Cameleon, the end of this 

 tongue is first slowly protruded to the distance of about an inch, 

 and then, with the rapidity of lightning, launched out with uner- 

 ring aim ; the fly, glued to its extremity, is with equal velocity 

 conveyed into the mouth. 



(613.) The jaws of the Chelonian Reptiles are not armed with 

 teeth, but cased in horny coverings so as to resemble the beak of a 

 bird, with which they crop the vegetable aliment upon which they 

 generally subsist. 



