56 Unizersity of Michigan 



PLATE IV 



The scales indicate a length of fifty microns. The relationships of 

 the centrals and laterals are represented as viewed. 



Fig. 15. Hclicina (Oxyrlwmhiis) conccntrica. Centrals, laterals, and 

 tip of 3rd uncinus. 



Fig. 16. Hclicina (Aiigiilata) caracoUa. Centrals and laterals. 



Fig. 17. LucidcUa (Lindsleya?) vciiczuclcusis. Centrals, and tips of 

 1st and 8th uncini. 



Fig. 18. Hclicina (Angulata) rliynchostonia crncsli. Centrals and tip 

 of 3rd uncinus. 



Fig. 19. LucidcUa (Pocuiclla) plicatiila. Centrals and tip of 3rd- 

 marginal. 



