SUCCINEA. 61 



ences in the structure of the organs of generation, and 

 notices the absence of the organs called by M. Cuvier, 

 vesiculce multifidoe, of the dart, and of the sack or pocket 

 in which the dart is contained. The want of these is, 

 however, by no means peculiar to Succinea. They are 

 equally wanting in all but one of the American species 

 of true Helices which have as yet been examined. 

 M. Deshayes here falls into an error too common among 

 naturalists, that of generalizing too much upon the few 

 species with which they are most acquainted. 



The habits of the animal do not vary much from those 

 of Helix. They are described in many works as being 

 amphibious, which means that they possess the power of 

 living in the water as well as upon the land. Such 

 appears to have been the opinion of M. Lamarck. They 

 are not, however, in any proper sense amphibious, as 

 they live upon the land exclusively, and breathe air; 

 and some of them occupy situations very distant from 

 bodies of water. It is not difficult, however, to account 

 for this general belief. Some of the species inhabit wet 

 localities at the borders of swamps and ponds, and are 

 even found attached to the leaves of plants growing out 

 of the water. They resemble also, in external charac- 

 ters, certain species of Limnea, which live in the water 

 itself. The two have, therefore, been confounded in pop- 

 ular belief. 



It is also stated very generally, that they cannot with- 

 draw their bodies entirely into their shells. This is cer- 

 tainly an error as regards the American species, and 



