1894.] NATI Ix'AI, SCIENCKS OF PHILADELPHIA. 61 



February 6. 



The President, General Isaac J. Wistar, in the chair. 



Thirty-seven ]iersons pi-esent. 



A paper entitled " Ol^servatious ou the Geology of adjacent parts 

 of Oklahoma and northwest Texas," by Edw. D. Cope, was pre- 

 sented for publication. 



A Neu> Central American Papa. — Mr. H. A. Pilsbry exhibited 

 specimens of a small land shell from Pol von, Nicaragua, and offered 

 the following description : 

 Pupa polvonensis n. sp. (PI. I, fig. 11). 



Shell cylindrical, somewhat tapering above, opaque gravish-white 

 with obli(]ue brown streaks. Whorls oh, somewhat convex; aperture 

 small, without intei-nal plica? or denticles; lip thin, simple, the 

 columellar margin dilated, partly concealing the round and rather 

 large umbilicus. Alt. 2, diam. 1-3 mm. 



This species resenddes I\ shnp/ex Gld. in the toothless aperture 

 and thin lips, but differs in coloration, the larger umbilicus, etc. 



February 13. 



The President, General Isaac J. Wistar, in the chair. 

 Thirty persons present. 



February 20. 



The President, General Isaac J. Wistar, in the chair. 



Thirty-nine persons present. 



The death of Edward 8. Whelen, a member, was announced. 



Papers under the folloAving titles were presented for publication : — 



" Tanais robustus, a new species of Auisopoda." By H. F. 

 Moore. 



" List of Port Jackson Chitons collected by Dr. Cox, with a re- 

 vision of Australian Acanthix-hitidse. " By Henrv A. Pilsbrv. 



February 27. 



Mr. Charles Morris in the chair. 

 Thirty-nine persons present. 



