MANUAL 



OP 



GEOLOGY; 



STRUCTURAL AND SYSTEMATIC. 



WITH ILLUSTRATIONS OF THE SPECIES. 



BY GEORGE W, TRYON, JR. 



CONTINUED BY 



HENRY A. PILSBRY. 



Vol. XI. 



TROCHID^, STOMATIID.E, rLEUROTOMARIID/E, HALIOTID^E. 



PHILADELPHIA: 

 Published by the Conehological Section, 



ACADEMY OF NATURAL SCIENCES, COR. igTH AND RACE STS. 



1889. 



LIBRARY 



UNIVERSITY OF CALIFORNIA 

 DAVIS 



