68 GASTROCOPTA, NORTH AMERICA, WEST INDIES. 



from, further west, the lip being very much thickened, as in 

 the type specimen of mcclungi. The specimen figured meas- 

 ures 2.4 mm. long, 0.95 wide. 



19. GASTROCOPTA CRISTATA (Pilsbry and Vanatta). PL 13, 

 figs. 6, 8 to 12. 



The shell is shortly rimate, cylindric, with convexly conic 

 summit, the apex obtuse ; glossy, brown, very finely, irregu- 

 larly striate. 5^ rather convex whorls, the last having a 

 strong whitish crest parallel to and behind the lip, and sep- 

 arated from it by a marked contraction. Behind the crest it 

 is somewhat flattened over the lower palatal plica. The aper- 

 ture has 5 teeth. The angulo-parietal lamella is not in the 

 least bifid in front view, but has an obtuse prominence on the 

 right side ; its angular component is very low, and weakly 

 connected with the outer lip ; the parietal is high, its anterior 

 end forming a scarcely noticeable projection on the columellar 

 side (pi. 13, fig. 9). The columellar lamella is rather short, 

 horizontal, and below it there is a low callous (sometimes 

 strengthened into a small but distinct tubercular tooth). The 

 palatal plicae stand within the lip-callous; upper and basal 

 ones are short, directly entering, lower plica deeply placed, 

 shorter than in B. procera. The plicae are visible on the out- 

 side as white marks behind the crest. The peristome is well 

 expanded and thin at the edge, but there is a rather thick, 

 pale brown callous rim a short distance within. 



Length 2.8, diam. 1.2 mm. 



Oklahoma: Fort Gibson (E. W. Hubbard) and Perkins, 

 Payne Co. (D. K. Greger). Texas: 15 miles southeast of 

 Amarillo ( J. B. Henderson) ; Pecos River drift, High Bridge, 

 and Rio San Filipe, Del Eio (Pilsbry and Ferriss) ; Laredo 

 (Orcutt) ; Hidalgo (Singley). New Mexico: Santa Fe; 

 Mountain station, Oscuro Mts., Socorro Co. (Ashmun) ; Me- 

 silla (Cockerell) ; Albuquerque and Mimbres River near 

 Deming (Pilsbry and Ferriss). Arizona: Navajo Springs; 

 Holbrook; Camp Verde, Yavapai Co., type loc. (Ashmun); 

 Salt River, Tempe ; Santa Cruz R. at Tucson and Amados ; 

 San Pedro River, Benson (Pilsbry and Ferriss) ; Barbakoma 

 Creek, Huachuca Mts. (Ferriss). 



