SECOND SERIES: PULMONATA. 



MANUAL 



OF 



CONCHQLOGY; 



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 OF 

 NATURAL SCIENCES OF PHILADELPHIA. 



Vol. 



HELICID^, Vol. IV. 



PHILADELPHIA: 

 Published by the Conehological Section, 



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

 1890. 



UNIVERSITY 



