ANIMAL LIFE IN PONDS & STREAMS 



If we examine one of these sponges in a watch 

 glass of water to which we have added a very little 

 carmine powder, we can easily see the water cur- 

 rents entering the pores and coming from the oscula. 

 Towards autumn, if we open a river sponge we shall 

 see little yellow bodies about the size of a pin's 

 head; they are the buds from which the young 

 sponges arise. One of these must be removed very 

 carefully and placed in a watch glass of water; if 

 our specimen be placed in the sun, we shall not have 

 many days to wait before we find that it has given 

 rise to an active transparent little creature, to a 

 young sponge in fact. By repeating our experiment 

 with carmine, by the aid of the microscope, we can 

 see the water currents passing through its body. 



Wherever we collect our pond water we are 

 certain to find some of the wheel animalculae or 

 rotifers. There are such a number of different kinds 

 that we might describe several, and yet not mention 

 the one that any of our readers had happened upon. 

 They may be recognised, because they are always 

 so transparent that all their internal organs may be 

 plainly seen and they always have two or more 

 discs or lobes, at their forward end, fringed with 

 fine whip-like threads. These little threads are 

 constantly in motion, so that they appear like little 

 revolving wheels hence the name, wheel animalcule. 

 Nearly all these creatures have a sucker or false foot 

 at their tail end by means of which they attach 

 themselves to some sup|X)rt or they may swim 

 freely in the water. The study of rotifers has been 



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