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 | 
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 ofthe country. They 
now grow with great rapidity during the remainder of the 
