COMMON FROG. 103 



Rusconi complains of having had considerable difficulty 

 in ascertaining the proper food for the Tadpoles, so as to 

 preserve them in health during his observations on their 

 developement. He found, however, by accident, that they 

 would thrive upon the green sediment which results from 

 the agitation of decayed vegetable matter in water ; and I 

 have succeeded completely in keeping them on the decay- 

 ing vegetable matter without any artificial preparation. 

 In their more advanced period, but still before the growth 

 of the extremities, they fed indifferently upon animal or 

 vegetable substances, actually gnawing away the substance 

 of almost any kind of leaf that was placed in the vessel, as 

 soon as it became softened. I have reason to believe, also, 

 that they often killed their own companions, as soon as 

 these, by the acquisition of their limbs, had nearly assumed 

 their ultimate form. Suspecting this, I placed in a large 

 glass globe of water, several Tadpoles, more or less nearly 

 approaching their final change, and I observed that almost 

 as soon as one had acquired its limbs it was found dead at 

 the bottom of the water, and the remaining Tadpoles feed- 

 ing upon it. This took place with all of them successively 

 excepting the last, which lived on to complete its change, 

 and for a considerable time afterwards. 



The little animal has now undergone its complete deve- 

 lopement ; and having become capable of respiring air by 

 true lungs, and of progressing with great freedom on land 

 by means of its hinder legs, it comes on shore to feed on 

 small insects and worms. Such multitudes of these newly 

 perfected little beings are often found in damp weather en- 

 joying their new scene of existence, as to have given rise to 

 many a story of its having rained Frogs ; a fable which is 

 still devoutly believed in many parts of the country. They 

 now grow with great rapidity during the remainder of the 



