400 
THE OCEAN WORLD. 
Certain species are also employed for feeding duets. Tlius, in ^ 
neighbourhood of Montpelier, ducks are fed upon Helix variabile an 1 * 
Figs. 1ST and 1SS. Helix Waltoni (Keeve). 
II. rhodostoma. Some fishes, especially the young salmon, are vetf 
partial to the flesh of snails. 
Fig. 189. Helix citrina (Linnasus). Fig. 190. Helix Stuartia (Soweilby). 
This very important genera is very numerous in species, which » J ' e 
distributed in groups according to the form of the shell ; that is, wheth ef 
Figs. 191 and 192. Bulimus sultanus (Lamarck). 
it be globulous, as in Fig. 184, tun-bottomed, as in Fig. 185, ph« ]1 01 
