SECOND SERIES: PULMONATA. 



MANUAL 



OF 



NCHOLOGY 



STRUCTURAL AND SYSTEMATIC. 



WITH ILLUSTRATIONS OF THE SPECIES. 



BY GEORGE W,(TRYON,)jR 



CONSERVATOR OP THE CONOHOLOOIOAL SECTION oFTB-4AHBJiY OF NATURAL 

 SCIENCES OF 



VOL. II. 



ZONITID^E. 



PHILADELPHIA: 



PUBLISHED BY THE AUTHOR, 

 Academy of Natural Sciences, Cor. 19th $ Race Sts. 



1886. 



