BIOLOGY 



The animals were more abundant, and in greater 

 variety. The creeping rotifers were most plentiful, and 

 there were several kinds of them besides the blood-red one 

 first noticed. Some were of curious shapes. 



Many were feeding, the two rotating wheels sweeping 

 streams of minute particles towards the mouth. 



Small bear-like creatures were scratching among the 

 debris or fiercely " pawing the air " with great curved, 

 dangerous-looking claws. These were the water-bears. 



Miniature snakes (thread-worms) were twisting in and 

 out, and lashing their tails. Some of the simplest of 

 animals (protozoa), each consisting of a single cell, were 

 there, the active infusoria swimming rapidly by means of 

 their cilia, the slower-moving rhizopods putting out their 

 little soft fingers to feed or creep about. Animals higher 

 in the scale were not wanting, though these were never 

 seen alive. Skins of some mites related to the cheese mite, 

 and of some small shrimps ( Crustacea) were occasionally 

 found. 



Among all these animals the rotifers and water-bears 

 were most important in point of numbers, and they lead 

 such strange lives that they will be more fully described 

 in later paragraphs. At any time during the winter an 

 unlimited supply of these animals could be got for study 

 by simply melting a piece of ice containing some weed. 

 In summer, the ponds and smaller lakes were completely 

 melted for weeks, and then they were still more easily got 

 by washing some of the weed. A few animals not found 

 in winter then hatched out from eggs and swam about in 

 the water. A large and beautiful rotifer named hydatina 

 appear in Coast Lake only. 



In Coast Lake also a curious thing happened in 

 summer. The stones at the margin became covered by 

 bright red patches, as though they had been sprinkled 



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