THE MICROSCOPE 



OCTOBKR, 1895. 



Number 34. 



New Series. 



Objects Seen Under the Microscope. 



XXVII. — THE FRESH WATER HYDRA. 



Translated from " Le Mlcrographe Preparateur." 



By chrysanthemum. 



There are three kinds of fresh water hydra in our 

 country; the green, hydra viridis, which has short arms, 

 their greatest length being about one-half that of the 



body ; the brown hydra, hydra fusca, which has long 

 arms, they being twenty-five millimetres or more in 

 length; and the gray or common hydra, hydra grisea or 

 vulgaris (fig. 1, 2), whose arms vary in length. 



