152 POLYGYRA. 



Near P. triodoutoides Bid., but with the umbilicus still more 

 obstructed, only the last part of the penultimate whorl visible 

 within it (as in P. ariadnai), the basal and external tooth nearer to 

 each other, and the latter more distinctly prolonged upward into a 

 lamina. (Mts.) 



P. DORFEUILLEANA var. SAMPSONI Wetherby. 



Differs from the type in having the umbilicus formed by the last 

 whorl much wider. It is more commonly found than the true dor- 

 feuilleana in Arkansas and Indian Territory. 



P. JACKSONI var. DELTOIDEA Simpson. 



Front margin of the parietal fold strongly elevated. 



Indian Territory. 



SCULPTARIA Pfr. (Vol. Ill, p. 138.) 



A group of unknown affinities. 



S. CHAPMANNI Ancey, Bull. Soc. Mai. Fr. vii, p. 156, (iinfigured). 

 Walwich Bay, Ovampoland. 



HELIX RETISCULPTA Martens, Nachr.-bl. D. M. Ges. 1889, p. 154, 

 (unfigurecT). Ussab, in Damaraland, S. Africa. 



STENOTREMA (Vol. Ill, p. 139). 



H. STENOTREMA Fer. (Vol. Ill, p. 140.) 



Var. subglobosa Pils. (pi. 50, figs. 26, 27). Spire lower than in 

 typical stenotrema, and color horn-brown, lips much developed, the 

 distal end of the parietal lamella being curved and produced 

 inward, the basal lip having a corresponding sinus, and on its outer 

 margin there is a small tooth. A short buttress from the parietal 

 lamella connects with the outer termination of the lip. 



Woodville, Alabama. 



H. MONODON Eack. (Vol. Ill, p. 142.) 



This species has several very distinct varieties. Var. cinda Lewis 

 (pi. 50, figs. 28-30) is very much depressed, with broad umbilicus, 

 brown at periphery and suture. Var. alicice Pils. is extremely 

 globose, elevated, closely coiled, imperforate or nearly so. It 

 inhabits the moist lowlands of south-western Louisiana, the figured 

 specimen being from Lake Charles. 



H. ELEVATA Say, (Vol. Ill, p. 148) read figs. 57-59, instead of 

 57-69. 



