74 
HELICID^. 
They have been distributed into sections in the 
following manner : 
§ 1. Scutifera. — Body elongate, attached the whole 
length of the foot; mantle shield-like, with a 
small internal shell. {Limacina^ 
1. Limax (fig. 29.). 
§ 2. CocMeophora, — Body more or less spiral, 
prominent on the (middle generally) upper sur- 
face of the foot, and covered with a more or 
less spiral shell. Sometimes partly hidden by 
the reflexed part of the produced edge of the 
mantle. 
* Mantle produced in fronts and partly extended 
over the shell. (Vitrinina.) 
2. Vitrina. Shell depressed, polished; mouth 
semilunar, large ; peristome thin. 
Mantle enclosed^ not produced in front. 
3. Zonites. Shell depressed, polished; mouth 
semilunar ; peristome thin, acute. 
4. Helix. Shell subglobose or depressed, striated ; 
mouth semilunar ; peristome rather thickened 
and reflected. 
5. Succinea. Shell oblong, elongate ; mouth very 
large, oblong ; peristome thin. 
6. Bulimus. Shell oblong, elongate, striated; 
mouth moderate, ovate, toothless. 
7. Zua. Shell oblong, elongate, polished ; mouth 
moderate, ovate, with a thickened internal 
edge. 
8. Azeca. Shell oblong, elongate ; mouth mode- 
rate, toothed, with a thickened internal edge. 
