Proc. Wash. Acad. Sci., Vol. VIII. 



Plate XI. 



* 5? 



» 3 

 ft fl* 



< O 



5'c 





5-i f 



r 3- (0 



8 t B 



?3 =2. 



° s> n> 



3-3* ^. 



O J U) 



^ n > 



* 2 rt: 



