826 Reptiles. 



Notes on the Frog. By R. Q. Couch, Esq., M.R.C.S.L. 



I very readily comply with your request, to state, through ' The 

 Zoologist,' what I have found to be the manner in which the frog 

 captures its food ; and, if not trespassing too much on the space 

 allotted to each subject, will add a few other particulars concerning 

 the frog, which are not generally known, and which may be interest- 

 ing to some of your readers. As far as regards the taking of their 

 prey, I have very little new to offer ; the general mode in which it is 

 effected is already recorded in works on the Reptilia. But some of 

 the variations are curious, and show that, low as they are in the scale 

 of nature, they yet possess resources to overcome difficulties, and tact 

 in accommodating themselves to their circumstances, which we could 

 hardly have anticipated. The appetite of the adult frog, like what I 

 stated was the case in their tadpole state (Zool. 677), may be called 

 carnivorous. They never live on a vegetable diet, but prefer slugs, 

 worms, and insects, chiefly of the coleopterous kinds ; and the quan- 

 tities they take are large, for their appetites are great, and digestion 

 rapid ; and hence they always feed when opportunities offer, and take 

 as much as they can procure. This voracity is, however, frequently 

 interrupted by long fasts, which they bear without much apparent 

 injury, even during the most active periods of the year. To under- 

 stand clearly the manner in which the food is taken, it should be 

 remembered that the tongue is not formed on the same plan as in the 

 higher animals, or is so remarkably modified as to have an entirely 

 different character. As the tongue lies in the mouth, the free portion, 

 which in man lies in front, is thrown backwards, and lies towards the 

 throat, being, in fact, doubled back on itself; the fixed point being 

 anterior to the free edge. When, therefore, the tongue is brought into 

 action, the free edge is elevated and thrown forward, so as to reach 

 considerably beyond the mouth. It is by this arrangement that the 

 food is taken ; for the frog possesses a power of directing its tongue 

 unerringly to any object it wishes to take. The rapidity with which 

 this is effected is so great, that it is not at all times easy to notice it, 

 unless within a foot or two of it at the time. The frog having selected 

 an insect for food, advances to it within the range of its tongue ; this 

 done, it squats with a great deal of composure ; its arms slightly ad- 

 vanced, its head erected, and slightly turned on one side, and its 

 bright and beautiful eyes fixed on the object of attack. In this atti- 

 tude it will sometimes remain for many minutes, waiting, apparently, 

 for a favourable opportunity. If the insect moves, or the opportunity 



