ACADEMY OF NATURAL SCIENCES. 335 



5 Vancouverensis Lea. Wh. 5, yellowish-green, shining, very slight 

 revolving grooves ; diam. 1.10 to * 1.25, axis 0.40. 



6 sportella Gould. Wh. 5, pale-greenish, growth lines coarse, crossed 

 by revolving grooves ; cfiam. *0.50 to 0.70, axis 0.20 to 0.25. 



7 Voyana Newc. Wh. 5, pale corneous, mouth much sinuated above, 

 body whorl crossed by a thick callus ; diam. *0.50, axis 0.15 to 0.20. 



Subfam. Gaslrodnntince. Generally depressed conic, and lamellarly 

 toothed inside, growth lines distinct, small. 



V Group. Conulus Fitz. minute, conoid, whorls 4 to 6, narrow, 

 aperture basal, transverse, perforate or not, without teeth. 



8 chersiua Say. Wh. 5-6, amber-yellow, imperforate, base indurated, 

 smooth, shining; diam. 0.10 to 0.12, axis, 0.08. 



chersinella Ball. Wh. i% to 5, yellowish, narrowly perforate, mouth 

 oblique, growth ribs distinct ; diam. *0.14, axis 0.09. 



Subfam. Patulince. Thickish, epidermis opaque, form discoidal to 

 subglobose, umbilicate, often striped or hirsute. 



VI Group. Pseudohyalina Morse. Minute, convex discoid, nearly 

 smooth, umbilicate, unicolor, whorls 3 to 5. 



10 milium Morse. Wh. 3, greenish white, plano-convex, translucent, 

 minute revolving grooves; diam. 0.05, axis 0.02. Nevada Co. and Angel 

 Island, Rowell, Monterey, Canfield, San Francisco and Santa Cruz, rare. No 

 revolving grooves seen. 



11 minuscula Binn. Wh. 4, whitish, nearly flat, mouth sub-oval, whorls 

 narrow, smooth, a parietal callus ; diam. 0.09, axis 0.01. 



12 conspecta Bland. Wh. 4, dark corneous, obtuse convex, smooth, 

 mouth sub-circular, oblique ; diam. 0.08 to 0.10, axis 0.04 to 0.05. 



VII Group. Patula Held. Size moderate, convex-discoid, concave 

 below, umbilicus showing all the whorls, unicolor. 



13 Hornii Gabb. Wh. A%, opaque, brown, sparsely hirsute, spire flat- 

 tened, umbilicus a little contracted ; diam. *0.16, axis 0.09. 



14 Whitneyi Newc. Wh. 4, smoky-brown, smooth, nearly flat, umbilicus 

 plainly perspective ; diam. *0.20, axis 0.10. 



15 Cronkhitei Newc. Wh. 4, yellowish corneous, a little convex, growth- 

 ribs distinct, not plainly perspective ; diam. *0.20, axis 0.15. 



16 striatella Anth. Wh. 3-4, pale corneous, depressed convex, umbilicus 

 large, shallow, growth-ribs faint ; diam. 0.20, axis 0.15. The west slope speci- 

 mens may be all of last species. 



17 Durantii Newc. Wh. 4. light corneous, flat above, nearly smooth, um- 

 bilicus perspective, opaque ; diam. *0.20, axis 0.07. 



VIII Group. Helicodiscus ? Morse. Planorboid, whorls visible 

 below, several sets of internal teeth. (" Polygyra" Tryon, part.) 



18 polygyrella Bland. Wh. 7 to 8, yellowish horn color, 3 teeth oppo- 

 site mouth, 3 nearer mouth, 1 parietal ; diam. *0.44, axis 0.19. 



