ANIMAL LIFE IN PONDS & STREAMS 



and watch it under our microscope we shall see it 

 expand, sending forth a number of stalks, each one 

 tipped with a horse-shoe shaped feathery tentacle. 

 Each of these tentacles belongs to a separate animal 

 which with its fellows forms a colony. Not so 

 interesting are the branched, threadlike colonies of 

 Plumatella Repens which may be sought upon the 

 leaves of water plants. Our ponds can furnish no 

 more extraordinary object for our microscope than 

 a colony of Cristatella Mucedo; it is curious in ap- 

 pearance and still more curious from the fact that 

 though a colony of animals it acts like a single 

 individual in crawling over the weeds and stones in 

 shallow, sun-kissed water. The Cristatella colony 

 is jelly-like and greenish in colour, in length it may 

 grow to a couple of inches. Its under surface is 

 flat, whilst from its upper, convex surface the little 

 animals forming the colony wave their brush-like 

 tentacles in the water. 



In searching the various pond weeds for specimens 

 we are sure to meet with various jelly-like masses; 

 these must always be examined carefully. They may 

 be the egg-masses of interesting water creatures; 

 various water-snails, for instance, protect their eggs 

 with a jelly-like covering. 



If we meet with any large fresh- water mussels, 

 sometimes called swan mussels, we shall probably 

 find the fleshy parts of the molluscs swarming with 

 minute creatures, which we may conclude are para- 

 sites. Mussels, like nearly all living creatures, have 

 their parasites it is true, but what we have dis- 



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