MANUAL 



OF 



CONCHOLOGY; 



STRUCTURAL AND SYSTEMATIC. 



WITH ILLUSTRATIONS OF THE SPECIES. 



BY GEORGE W, TRYON, JR. 



CONTINUATION BY 



HENRY A. PILSBRY, 



CONSERVATOR OF THE CONCHOLOGICAL SECTION OF THE ACADEMY OF 

 NATURAL SCIENCES OF PHILADELPHIA. 



Vol. XVI. 



GASTROPTERID^, AGLAJID^, APLYSIID^, 

 OXYNoEID^E, RUNCINID^E, UMBRACULID^, 

 PLEUROBRANCHID^:. 



PHILADELPHIA : 

 Published by Coixcliological Section 



ACADEMY OF NATURAL SCIENCES, 

 OF PHILADELPHIA. 



1895-6. 



LIBRARY 



UNIVERSITY OF CALIFORNIA 

 DAVIS 



