HELIX. 139 



the aperture, but seen through the shell, upon the parietal wall are 

 three revolving laminae, and upon the columella another; base 

 flattened, umbilicus small, impressed. Diam. 2'5 mill. 



Maine to Maryland, Florida, Mississippi, Texas, Arkansas, 

 Western 'States, Mexico. 



The last locality is for H. Strebeli, Pfr. (fig. 48) which is now 

 generally considered a synonym. 



Var. MORSEI, Ball. 



Differs from the type in wanting the costse, the whorls being only 

 lightly striate, rather flat and appressed, with the basal periphery 

 particularly angular and the umbilicus slightly smaller. 



Porto Cabello, Venezuela. 



H. HUBBARJ?!, A. D. Brown. PI. 29, figs. 49-52. 



Depressed, thin, striate above, smooth beneath, brownish ; whorls 

 5, with two parietal revolving laminae, and two, more deep-seated, 

 on the outer whorl ; umbilicus rather wide ; lip slightly reflected. 



Diam. 2'25 mill. 



Georgia, Florida, Indianola, Texas; Jamaica. 



H. Vendryesiana Gloyne (figs. 51, 52) from the last-named locality, 

 is a-synonym. 



*** 



H. LEIODA, Hutton. (Unfigured). New Zealand. 



Section IV. STENOTREMA, Rafinesque, 1819. 



The shells brought together under the genus Stenotrema of 

 Rafinesque are readily arranged in four groups: First, the group 

 including Edvardsi and barbigera characterized by the extraordinary 

 development of the epidermal hairs. Second that formed by spinosa, 

 and Edgariana equally Avell characterized by the sharp periphery 

 of the body whorl and the prostrate epidermal hairs. Third the 

 group containing hirsuta, stenotrema, labrosa, and maxillata, in 

 which the epidermal processes are shorter, and the surface is more 

 tuberculate. Fourth, the group containing monodon, fraterna, Leaii, 

 and germana. Among themselves the species in each group are 

 united more or less closely, those of the monodon group being 

 usually regarded as varieties of that shell, with the exception of 

 H. germana, which Mr. Binney finds to be related to Stenotrema by 

 its jaw and dentition, and more nearly to Mesodon by its shell; 

 a prominent character of which is the want of the internal tubercle. 



