PROC. ACAD. NAT. SCI. PHILA. I 



PLATE X. 



V.m 



24 



m 



15 



17 



18 



fifi! 



19 



21 





20 



22 



26 





26 



27 



Pilsbry and Vanatta del. 



PILSBRY AND VANATTA. NORTH AMERICAN SLUGS. 



