STENOPUS. 221 



side. Foot long and narrow, abruptly truncated behind, and 

 furnished with a distinct, mucous, caudal gland. 



Shell external, spiral, well-developed. 



In this family the mouth is provided with a serrated homy 

 jaw, and the lingual dentition appears to be similar to that 

 of the Helicida, from the animals of which family, however, 

 the lobate, extended mantle-margin will distinguish them ; 

 from the Vitrinina the muciparous pore and posterior trun- 

 cature of the foot will at once separate them; while the spiral 

 fomi of the body, protected by an external, well-developed 

 shell, will prevent their being confounded with the Arionida, 

 which seem to bear the same relation to the Stenopida that 

 the True Slugs do to the Helicida. 



Genus STENOPUS, Guilding. 



Front edge of mantle large, closing the mouth of the 

 shell. Foot truncated behind, with a sub-retractile ap- 

 pendage having a gland at its base ; sole linear, narrower 

 than the foot. 



Shell perforate, conical or depressed, thin, diaphanous ; 

 whorls 5 6, the last much the widest ; aperture roundly 

 lunate ; peristome simple, acute, the columellar margin 

 involute. 



Ex. S. cruentus, Guilding, pi. 79, fig. 4. Shell, S. 

 cruentus, fig. 4, a. 



Stenojnis, which differs from Nanina in the narrow sole 

 of the foot, consists at present of but two species, viz. 

 8. cruentus and 8. lividus, both discovered by Guilding in 

 the Island of St. Vincent, living among dead palm leaves. 



Vol.. II. (i ,; 



