HELIX. 143 



H. GERMANA, Gould. PI. 29, figs. 79-81. 



Solid, imperforate, whorls 5, narrow, subangular at the periphery, 

 very convex below ; aperture narrowly transverse, parietal wall with 

 a long blade-shaped tooth ; horn color, with a few scattered hairs. 



Diam. 7*5 mill. 



Oregon. 



The base is more convex than in H. monodon, and is not indented 

 around the axis. 



Section V. TRIODOPSIS, Rafinesque, 1819. 

 Subsection I. TRIODOPSIS, (sensu stricto). 



H. TRIDENT AT A, Say. PI. 29, figs. 82-84. 



Whorls 5-6, a little convex, obliquely ridged-striate, aperture 

 trilobate, lip widely reflected with a small marginal tooth on the 

 upper and another on the basal portion, parietal wall with an oblique 

 tooth, base convex, umbilicus open and deep ; yellowish horn color, 

 lip milk white. Diam. 13-23 mill. 



Canada, United States east of the Rocky Mts. 



Triodopsis lunula, Raf. teste Fer., is a synonym. 



Generally larger than the next species, with more depressed form 

 and much smaller teeth. 



H.. FALLAX, Say. PI. 29, figs. 85-87. 



Whorls 5, moderately convex, obliquely ridged-striate; aperture 

 trilobate, the parietal lamelliform tooth large and oblique, the lip 

 teeth large and flattened, the upper one deflected into the aperture ; 

 base moderately convex, umbilicus open ; light horn color, lip white. 



Diam. 11 mill. 



United States, east of Rocky Mountains. 



Dr. Binney included this species in H. tridentata, as a variety ; 

 it differs in its smaller size, more elevated spire and larger teeth. 



H. LEVETTEI, Bland. PI. 29, figs. 88, 89. 



Umbilicated, thin, shining, translucent, irregularly, slightly, 

 obliquely striated, suture impressed ; whorls 7, the last a little deflec- 

 ted at the aperture, behind which it is constricted, obsoletely spirally 

 striated ; aperture with a transverse parietal tooth, an obtuse mar- 

 ginal tooth on the right side, and two transverse basal teeth, the 

 upper one larger, peristome pale chestnut colored, its margins joined 

 by a slight callus. 



Near Santa Fe, Neiv Mexico. 



