PLATE IX. 

 [Proc. Wash. Acad. Sci., Vol. IV, PI. VII.] 



FIG. 25. Aphorura octopunctata Tull.; right postantennal organ, etc. ( X 367). 



26. " " dorsal aspect of right antennal organ 

 ( X 434). 



27. Aphorura octofunctata Tull.; left aspect of left hind foot ( X 367). 



28. " " " left aspect of left anal spine ( X 357)- 



29. " dentata sp. nov.; represents arrangement of dorsal pseudo- 

 celli ( X 20). 



30. Aphorura dentata sp. nov. ; right postantennal organ ( X 434)- 



31. " " " " deeper structure of postantennal organ 

 (X434)- 



32. Aphorura dentata sp. nov.; base of right antenna ( X I2 7). 



33. " " " " dorsal aspect of right antennal organ 

 (X434)- 



34 Aphorura dentata sp. nov. ; left aspect of right hind foot ( X 200). 



35. " " " " dorsal aspect of anal spines ( X 2Oo).f 



36. " " " " right aspect of right anal spine ( X 200). 



37. Isotoma fmetaria (L.) Tull.; antenna ( X 60)- 



38. " " " " left aspect of right hind foot ( X 434)- 



39. " " " " left mucro ( X 434)- 



40. " viridis Bourl., var. arctica Schott; eyes and postantennal or- 

 gan of right side ( X 200). 



41. Isotoma viridis Bouri., var. arctica Schott; left aspect of left fore foot 



( X 200). 



42. Isotoma viridis Bourl., var. arctica Schott; right aspect of right 

 mucro ( X 434)- 



[114] (" 2 ) 



