124. Shell distinctly higher than wide 125. 

 Height about equal to, or less than, width 153. 



125. Aperture toothed or with the outer side of margin reflected 126. 

 Aperture toothless; lip thin 136. 



126. Aperture round and toothless; edge of aperture completely reflected all 



around; about ^2" ^ig^ 127. 



Edge of aperture incomplete across the parietal wall 128. 



127. Body whorl curved, disjoined; aperture almost circular; southeastern 



states 



Cochlodinella poeyana (Orb.) 

 {IJrocoptis poeyana (Orb.) ) 

 {Cylindrella poeyana (Orb.)) 

 Body whorl keeled below and scarcely or not disjoined; aperture some' 

 what squarish; southwestern states 

 Holospira roemeri (Pfeiffer) 

 (Cylindrella roemeri Pfeilfer) 



128. Shell narrow, tapering; with more than seven whorls; aperture toothless; 



about 1/2" to y/^; southern states 



Microceramus pontificus (Gould) 

 (Macroceramus pontificus (Gould) ) 

 Shell more cylindrical, approaching capsulcshaped; whorls may or may 

 not exceed seven; toothed or toothless 129. 



129. Shell very thin and transparent, minute; aperture with about two teeth; 



with one pair of tentacles, with eyes at their bases; generally distributed 



Carychium exiguum (Say) 



Shell translucent or opaque, usually rather solid; large or small; toothed 



or toothless; with one or two pairs of tentacles, with eyes at the ends 



of the single or larger pair 130. 



130. Shell white or streaked with color; about 1" high; Florida 



Cerion incanum (Binney) Giant Pupa Shell 

 Usually plain brownish colored; usually much smaller; more generally 

 distributed; Family Pupilhdae ■ — Pupa Shells 131. 



131. Shell widely umbilicate, with a hollow axis to apex; Arizona 



Chaenaxis tuha (P. & F.) 



Not so; more generally distributed 132. 



132. With only one pair of tentacles 133. 

 With two pairs of tentacles, the lower pair minute 134. 



133. Tooth or lamella on parietal wall nearest outer edge of aperture not 



reaching to junction of lip with parietal wall 

 Vertigo ovata Say 

 Tooth or lamella on parietal wall nearest outer edge of aperture reach' 

 ing to junction of lip with parietal wall 

 Ster\ia hemphilli (Sterki) 



134. Usually with five or more teeth in the aperture; teeth on parietal wall 



usually joined together 



Gastrocopta armifera (Say) 

 (Bifidaria armifera (Say) ) 

 Usually toothless or with one small tooth 135. 



129 



