ANIMAL LIFE IN PONDS & STREAMS 



digested all he can he flows away from the un- 

 digested portions; he has no mouth or any of the 

 organs usually associated with animal anatomy. 



While hunting for our Amoeba, it is highly prob- 

 able that a very active little slipper-shaped organism 

 may have forced himself upon our attention. From 

 his shape he has earned the popular name of the 

 slipper animalcule. He is rather more highly organ- 

 ised than the Amoeba for he possesses a mouth, as 

 we shall see when we are able to examine him. So 

 rapidly does he swim, however, that something must 

 be done to curb his activity; he may either be 

 killed with a drop of weak acid or we may put 

 a little tuft of cotton wool on our drop of water 

 and a coverslip lightly over that. The threads of 

 cotton wool will form a network, in the meshes of 

 which the active little animalcule will be confined. 

 Careful observation will show that he is, like a 

 slipper, more pointed at one end than at the other; 

 that there is a funnel-shaped orifice, his mouth, at 

 one side of his body ; and that he is covered with 

 little threads which lash the water with rhythmic j 

 movement and propel him with considerable rapi- i 

 dity. These little threads also send currents of water 

 to his mouth, and in the water is his food. 



Having examined these two free swimming deni-i 

 zens of the pond, we may advantageously turn our 

 attention to some of the weeds growing therein, jj 

 Careful examination with our pocket lens will almost! 

 certainly reveal a number of minute living creatures!^ 

 attached to the submerged stems and leaves. It 



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