PACIFIC COAST SPECIES. ' If)! 



Arionta Stearnsiana, Gabb. 



Shell narrowly umbilicated, subglobose, solid, of a dirty-wliite color, 

 irregularly mottled with crowded ashy blotches^ ^^^ ^g^ 



grouped into revolving series below, with a decided, 

 wide, brownish revolving band above ; with delicate, 

 oblique incremental strife, unequally cut by revolv- 

 ing lines;* spire elevated; whorls 5, rather convex; 

 aperture oblique, semicircular; peristome simple, 

 acute, its columellar termination white, expanded, 

 reflected over the half-concealed umbilicus. Greater 

 diameter 22, lesser 17""" ; height, 12™"'. 



Helix Stearnsia7)a, Gabb, Am. Journ. Conch., iii, 235, pi. svi, 



fig. 1 (1867).— W. G. BiNNEY, L. & Fr.-W. Sh., i, 177, 



fig. 310 (1869). — Fischer and Crosse, Moll. Mex. et , , 



" , . . A Stearnbiana 



Guat., 248, pl.xi, fig. 5, 5a (1870). 



Arionta Sfeariisiana, W. G. Binney, Terr. Moll., v, 362. 



A species of the Mexican fauna, common in Lower California, from 

 San Tomas Elver, Todos Santos Bay, Coronado Island, Todos Santos 

 Island; admitted here because it is found plentifully within the limits 

 of the California Eegion around San Diego. 



The shell figured and described was received from Dr. Newcomb. 

 It is entirely mature. 



The genitalia (Terr. Moll., V, Plate XIII, Fig. B) resemble very 

 nearly those of KelletU. A comparison of the figures, however, will 

 show considerable difference, especially in the dart sac (13). In the 

 species before me there is a long, thread-like duct leading from the 

 base of the dart sac to a large globular organ (H:"^), whose character is 

 unknown to me. Opposite the entrance of this duct a corresponding 

 duct (IS'^) branches out, but instead of ending in a globular organ it 

 becomes much enlarged in size and ends in enveloi)ing the ])repuce 

 {p p). The dart sac contained a small dart of the form figured by Leidy 

 (Terr. Moll. U. S., I) for TehennopJioriis Garoliniensis. The oviduct 

 was closely and spirally wound around the duct of the genital bladder. 

 The testicle and ovary are yellow. 



Theja^^ is thick, arched, ends blunt, but little attenuated; anterior 

 surface with G stout, separated ribs, denticulating either margin, and 

 several less de^•eloped, interstitial ribs. 



The lingual membrane is long and narrow, with about oO-l-oO teeth. 

 The centrals are of the form usual to the genus. The cusp, with its 



*The revolving lines are absent in numerous specimens examined by me. 



