HYDRA. 75 



us, it is rather a pretty object ; but if one casts 

 about for a similitude it is rather difficult to find 

 one. The knotted cat-o'-nine-tails supplies a not 

 inapt comparison, both as to form and function. 

 A handle with knotted cord or thongs at one end, 



FIG. 12. Hydra fusca on anacharis. 

 A. Natural size expanded. B. Natural size contracted. 



when wielded with a strong arm and falling on the 

 back of a criminal, is said to sting ; and here is an 

 animal just of this form : a hollow or sub-cylin- 

 drical body, with from five to ten slender serrated 

 or knotted-like arms springing from its head, 

 each armed with poisonous stinging organs, which 

 spring out with marvellous velocity at the moment 

 of impact with its prey killing some at once and 



