SECOND SERIES: PULMONATA. 



MANUAL 



OP 



J 



ONCHOLOGY; 



STRUCTURAL AND SYSTEMATIC. 



WITH ILLUSTRATIONS OF THE SPECIES. 



BY GEORGE W, TRYON, JR. 



CONTINUED BY 



HENRY A. PILSBRY. 



CONSERVATOR OF THE CONCHOLOGICAL SECTION OF THE ACADEMY OP 

 NATURAL SCIENCES OF PHILADELPHIA. 



Vol. 



HELICID.E, Vol. VI. 



PHILADELPHIA : 

 Published by the Conehologieal Section, 



ACADEMY OF NATURAL SCIENCES, COR. IQTH AND RACE STS. 

 1892. 



