MANUAL 



OP 



CONCHOLOGY; 



STRUCTURAL AND SYSTEMATIC. 



WITH ILLUSTRATIONS OF THE SPECIES. 



BY GEORGE W. TR YON, JR. 



(Axv.-.ui-.VATois, C.F ',-.:;: ( V^VTIOLOOTCAT, Sr.r-riox OF 'I-T- ArLvnvAfv OB- NATURAL 



UNIVERSITY, 



MARGINELLID^l, OLIVID^E, 



PHILADELPHIA: 

 Published by the Aiithor, 



AQADEMY OF NATURAL SCIENCES, COR. I9TH & RACE STS. 



1883. 



