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SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Ill 



Fig. 20. — Ludius fallax group. 

 a, be, Ludius tessellatus (Linnaeus): a, ninth abdominal segment, dorsal 

 view ; b, nmth and tenth abdominal segments, lateral view ; e, left urogomphus, 

 lateral view, c, L. castaneus (Linnaeus) : urogomphi, dorsal view, d, f, L. 

 bombycinus (Germar) : d, urogomphi, dorsal view (drawn from larval exu- 

 vmm) ; /, left urogomphus, lateral view (drawn from larval exuvium). 



