[33] 



Zbc Development anb Xife^lbietor^ of the 



^abpole. 



By J. W. Gatehouse, F.I.C. 



Fart I. 



Plates I and II. 



FOR some few years past it has been my custom during the 

 spring time to devote a certain amount of attention to the 

 development of the frog, obtaining for this purpose the 

 spawn in as early a stage as possible, and keeping it under various 

 conditions, so as to watch, with the unaided eye, as well as by 

 means of the microscope and chemical balance, the various 

 changes which the animal undergoes during its metamorphoses. 



Although most of our best physiologists have written on the 

 same subject, there seems on several points, and especially as to 

 the nature of the food of the tadpole, a great divergence of 

 opinion, some averring that it feeds on vegetable diet, whilst others 

 are equally certain that it eats animal food. 



Buckland, in his " Curiosities of Natural History," states that 

 tadpoles eat both decaying animal and vegetable matters, in 

 addition to being cannibals and eating each other. His words are 

 well worth quoting :— " In the horse-pond were many tadpoles 

 hustling and squeezing each other in their anxiety to get a dead 

 kitten. And why should they not fight for good places? The 

 dead kitten is to them what a turtle dinner is to the city folks ; 

 each duly appreciated by the rightful customers. But supposing 

 there happen to be no dead kitten or decayed vegetable matter in 

 the pond, what will the poor things get to eat ? Why, they will 

 do what the New Zealanders have done before them — viz., ate up 

 every specimen of the Dinornis they could find on the islands, 

 and then they set to work and ate up each other ; so do the tad- 

 poles." There is this difference, however, between the New 

 Zealanders and the tadpole, that whereas the former killed his 

 brother previously to breakfasting off him, the tadpole waits till 

 he is dead before he commences to make his meal. 



Hu.xley takes the opposite view. In the " Course of Practical 



New Series. Vol. I. D 



1888. 



