1906.] NATURAL SCIENCES OF PHILADELPHIA. 557 



PUPrLLIDiB. 

 Ptipoides marginatus (Say). 



Rogers, Benton Co., Ark.; Limestone Gap, Choctaw Nation, I. T. 

 Bifidaria contraota (Say). 



Rogers, Benton Co., Ark.; Limestone Gap, I. T. 

 Bifidaria armifera (Say). 



Chadwick, Christian Co., and Monette, Barry Co., Mo.; Rogers, 

 Benton Co., Ark. ; Vinita and Limestone Gap, I. T. 

 Bifidaria procera (Gld.). 



Rogers, Benton Co., Ark. 

 Bifidaria pentodon (Say). 



Hillside along creek south of Blue Mountain Station, Logan Co., Ark. 



Vertigo rugosula Sterki. 



Limestone Gap, L T., one specimen. 



Strobilops labyrinthioa texasiana Pils. and Ferr. 



Wyandotte and Limestone Gap, L T. (Ferriss and Pilsbry); Fort 

 Gibson (Hubbard). Silver Lake, Kan., and Pottawatomie Co., 

 Okla. (J. B. Quintard). 



VALLONIIDiE. 



Vallonia parvnla Sterki. 



Fort Gibson, Cherokee Nation, L T. (E. W. Hubbard, Coll. A. N. S. 

 r.). This is the only Vallonia we have seen from Arkansas or Indian 

 Territory. No other species or locality has been recorded. 



OIRCINARIIDJE. 



Circinaria concava (Say). 



Chadwick, Christian Co., Mo. Magazine Mt., Logan Co., Ark., 

 north side of the summit; also on the south side. 



ZONITIDiE. 



Gastrodonta ligera (Say). 



We took this snail at Vinita, Cherokee Nation, I. T., in abundance. 

 We have also seen specimens from Fort Gibson, L T., taken by Mr. Simp- 

 son in 1888. These points mark its western limit so far as known. 

 Mr. Sampson reports it from five counties in Arkansas {Moll, of Ark., 

 p. 182). It is not known from southern Arkansas or Texas. 



In Louisiana and the adjacent part of Texas G. intertexta replaces 

 ligera in the low country, but that species has not been found in the 

 Ozark region. 

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