The Zoologist— Dfxember, 1869. 1989 



their bearing on inetamorphosis. I now revert to the tadpole, con- 

 cerning which, and as to its being in the ordinary course of nature a 

 larval or imperfect frog, there can be no doubt. The food of this 

 familiar object has been gravely discussed and much disputed: in 

 reply to a question by Mr, Chennell on this subject, I received the 

 following conclusive observations from the pen of Mr, Richard Quain 

 Couch, a gentleman whose early death was a severe loss to the science 

 of Natural History, and one perhaps never to be repaired. 



" In answer to your correspondent, Mr, Chennell (Zool. 579), on 

 the subject of the food of the tadpole and the frog, I beg to offer him 

 ray experience on ihe point in question. Soon after the tadpole has 

 effected its liberation from the spongy envelope of the egg, it adheres, 

 by means of a pair of hooks on the breast, either to the empty egg or 

 to some other substance near ; although it is frequently found lying 

 on its side at the bottom of wells or ditches. In this state it is 

 entirely inactive, or at most its activity consists in only occasionally 

 flapping its tail : at this stage it takes no food, and must therefore 

 be nourished by the remains of egg within it. As the temporary ex- 

 ternal branchiae disappear, the tadpoles become more and more active, 

 and proportionably more voracious. At this time they very actively 

 search for food, though they do it without the least intelligence : they 

 generally, when in confinement, place their mouths against the bottom 

 of the vessel, and search indiscriminately in all directions to obtain it: 

 and although on many occasions food was designedly placed near 

 them, yet they never, in any instance, turned to it as if they perceived 

 it either by sight or smell, but came upon it by accident : so it is 

 also where they are at liberty in the ponds and ditches. They are 

 said by some authorities to prefer a vegetable diet, and from some 

 accounts indeed they might be supposed to reject all animal food; 

 this, however, does not appear to be the case. In those which I have 

 kept in confinement, I found that when I fed them on the water-cress, 

 supposed to be their favourite food, they lived contentedly on it for 

 about twenty-four hours, and then the strongest would attack their 

 weaker companions, and in the end devour them. This act of 

 cannibalism was generally prevented by feeding them on animal diet, 

 but still they always showed a preference for their weaker com- 

 panions. During the earlier stages of their development they are very 

 active and voracious, but as the development goes on and the arms 

 and legs are getting useful for progression they get very inactive, 

 and their appetite nearly leaves them. In this state they lie very 



