130 SUPPLEMENT ON ANNELIDA. 



and stomach found in the blood-sucking leeches, but digestion 

 is extremely slow in all. 



The leeches are essentially aquatic animals, most of them 

 living in fresh water, but some in the sea ; a few occasionally 

 quit the water, and as nature seldom acts on a single rule, one 

 species is said never to go into it — humidity, however, is as 

 necessary even to these as to the earth-worms. 



We have nothing to add on the genus Gordius, and proceed 

 therefore to the translation of Cuvier's description of such of 

 the articulated animals as have articulated feet. 



