U, S. NATIONAL MUSEUM 



PROCEEDINGS, VOL. 57 PL. 19 



:"^,^^%, 



,^ 



'/'* 



i ■'■ ^ 



■'-4. 



I 



I \ ( 



■i •,. '» ; 



i 







u 



U"'- 



/i:^'^^ 



^/■y' 





The Structure of Iridia diaphana. 



For explanation of plate see page 157. 



