THK NAUTILUS. 115 



Note. — Under the synonymous name Stenogyra suhvla Pfr. this 

 species was reported from Mobile by W. G. Binney, Manual of 

 American Land Shells, p. 426, noted in Man. Conch., vol. 18, p. 

 199. 



0. gracile was taken by Mr. C. T. Simpson and myself on Key 

 West in 1907. It is particularly abundant in the cemetery. It was 

 not found by us on the other Keys, and did not turn up in the copi- 

 ous collections made by Mr. Moore in the Ten Thousand Islands. 

 It seems likely, therefore, that the species was introduced by com- 

 merce at Key "West and Mobile. Binney also speaks of it as 

 " introduced." — Ed. 



DBIFT SHELLS FROM TEXAS. 



BT V, STERKI. 



Mr. Bryant Walker has kindly sent me a portion — about half a 

 pint — of fine drift siftings, gathered from the Paluxy Creek, at 

 Glenrose, Somervell Co., Texas, southwest of Fort Worth. It con- 

 tained a large number of mollusk shells, of various groups, many of 

 which are interesting with respect to distribution, or systematics, or 

 both, as the list will show. 



Zonitoides arhoreus (Say), a few, juv. and immature. 



Z. minusculus (Binn.), numerous and variable ; mainly two forms : 

 one with the whorls narrow and the umbilicus very wide, especially 

 by the last whorl receding outward towards the aperture, and even 

 ascending above on the penultimate ; the other with the whorls 

 wider and the umbilicus narrower. Beside these, there are a few 

 specimens very small, with narrow whorls. 



Z. Icevuisctdus (St.). numerous, but few specimens full-sized. 



Z. singleyanus (Pils.), var., numerous, somewhat variable. 



Z. nummus (Van.), about 40. 



Z. milium (Mse.), about 30. 



Vitrea indentata (Say), a few dozen, juv. and half-grown. 



V. dalliana roemeri (Pilsbry), about a dozen. 



Helicodiscus lincatus ("Say), a few. 



Punctam pygmczum (Drap.), about 150. 



