174 THE MICROSCOPICAL NEWS. 
Development is now complete. Our fish-like tadpole has now 
become an amphibious animal. The metamorphosis of No, 1 
tadpole is now complete in 74 days; No. 2, not until go days; 
No. 3, 118 days; whilst No. 4 only gets to the concluding stage 
in 180 days. 
You will observe in these results a difference of 106 days against 
the purely vegetable feeding theory. ‘The metamorphosis of No. 1 
is thus extended by No. 4, 1% times; and, I may add, that this 
has been my experience for at least seven years. But further, in 
support of my conclusions, I have carefully observed the ponds 
from which I got my spawn, and have frequently found the young 
frogs hopping on the grass, at the edge.of the pond, at 98 days. 
In my experiments with No. 3 they take 118 days. You will readily 
see there is more chance of the tadpoles catching animalcules in a 
pond than in a small vessel, which amply accounts for the 
difference of 20 days, but with No. 2 only eight days. 
I shall not trouble you with a long list of opinions as to the 
vegetarian habits of the tadpole, but shall adduce the following as 
sufficient. Mungo Ponton says :—‘‘The tadpole in due time 
becomes gradually prepared.for an entire change in its manner of 
life and outward aspects. It has to alter its mode of respiration 
from aquatic to atmospheric, and its diet from vegetable to 
animal.” Dr. Andrew Wilson says:—‘The tadpole possesses 
horny jaws by which it crops the water weeds, for although the 
adult frog is an insect eater the youthful frog is a strict vege- 
tarian ; and coiled up within its body we may perceive the spiral 
and lengthy intestine proper to the plant-eating form.” Dr. 
Carpenter also favours the vegetarian side, although he admits 
they do take animalcules. After this weight of evidence it is 
difficult to see how I can hope to convince you of its falsity ; yet 
any one may have clear proof that it is false by getting a few tad- 
poles, kill one, or a stickleback, and put in with them. They 
will at once give evidence that they are well adapted to devour 
animal food with avidity. So much so, if one happens to 
die there is no need to make any arrangement for a funeral, 
as they seem to take a particular interest in a defunct relative. 
Further, if one shows any signs of sickness the whole community 
watch the result with extreme interest, and, in addition to this, 
the strong ones generally give the sufferer a loving squeeze or nip, 
just to help forward the catastrophe which they seem to know will 
give them a good feed. In Sctence Gossip for March, 1880, Mr. 
M. H. Robson, Hon. Secretary of the North of England Micro- 
scopical Society, supports my conclusions when he says, “ Light 
appears principally necessary as a stimulus to the growth of vegetation 
and production of infusoria upon which they (the tadpoles) seemed 
chiefly to subsist.” He also names 117 days as the time taken to 
