

POI.YGYBA. 



73 



cc. Size small ; whorls 6, the last contracted in its first half, 

 its last half notably swollen. carpenteriana. 



bb. No internal lamina. 



c. Upper surface coarsely ribbed. 



d. Size large, whorls 7 or more. septemvolva. 



dd. Size smaller, whorls 51-7, volvoxis. 



cc. Upper surface very finely striated. microdonta. 



P. cereolus Muhlf.,iii, 128. 

 laminifera W. G. B. 



/. carpenteriana Bid. 



microdonta W. G. B., olim. 

 /. septemvolva Say. 



planorbula Lam. 



polygyrata " Binn." Pfr. 

 /. volvoxis Pfr. 



febigeri Bid. 

 /. floridana Hemph. 



Var. microdonta Desh. 



delitescens Shutt., undesc. 



cheilodon Say, Bid. 



/ plana Dkr. 

 P. paludosa Pfr. iii, 129. 



lingulata Fer., Dh. 



ramonis d'Orb. 



ramondi d'Orb., Atlas. 



imularum Beck, undesc. 



f bardenflehtii B., Villa. 



Species with teeth on the outer lip. 



With the exception of P. johannis of Cuba, the species of this sec- 

 tion are all continental. The auriculata series inhabits the southern 

 tier of Gulf States, from Florida to Texas ; the dorfeuilliana series 

 is confined to the more or less mountainous region south of the Ohio 

 River, from Tennessee to Oklahoma; the texasiana acutedentata 

 series is from Mexico, extending into Texas along the northern 

 continuation of the Sonoran fauna and flora. 



P. auriculata Say, iii, 137. 



v. microforis Dall, iii, 138. 

 P. uvulifera Shutt., iii, 137. 



florulifera Rve. 

 P. auriformis Bid., iii, 137. 



f sayii Wood, DeKay. 



P. hazard! Bid., iii, 131. 



plicata Say. 



f finitima Dh. 

 P. dorfeuilliana Lea, iii, 133. 



v. sampsoni Weth., viii, 152. 



P. postelliana Bid., iii, 137. 

 P. espiloca (Rav.) Bid., iii, 136. 

 P. avara Say, iii, 136. 

 P. pustula Fer., iii, 131. 

 P. pustuloides Bid., iii, 132. 

 P. leporina Old., iii, 131. 

 # 



P. fastigans Say, iii, 131. 



fatigiata Say. 



fastigiata DeK. 

 P. jacksoni Bid., iii, 134. 



v. deltoidea Simp., viii, 152. 

 P. troostiana Lea, iii, 131. 



