SECOND SERIES: PULMONATA. 



MANUAL 



OP 



CONCHOLOGY; 



STRUCTURAL AND SYSTEMATIC. 



WITH ILLUSTRATIONS OF THE SPECIES. 



GEORGE W, TRYON, JR. 



CONTINUATION BY 



HENRY A. PILSBRY, 



CONSERVATOR OF THE CONCHOLOGICAL SECTION OF THE ACADEMY OF 

 NATURAL SCIENCES OF PHILADELPHIA. 



Vol.* XI. 



AMERICAN BULIMULID^e : BULIMtJLUS, NEOPETR^US, 

 OXYCHONA, AND SOUTH AMERICAN DRYM^US. 



PHILADELPHIA: 

 Published by Conchological Section 



ACADEMY OF NATURAL SCIENCES, 

 OF PHILADELPHIA. 



1897-8. 



