AMERICAN ODONATA. 217 



Fig. 16. — Same of Gomphus amnicola Walsh. Rock Island, 

 Illinois, Type 1010, U. S. Nat. Mus. 



Fig. 17. — Same of Gomphus notatiis Rambur. Cumberland River, 

 Nashville, Tenn., September 30, 1900. E. B. Williamson. 



Fig. 18. — Same of Gomphus spiniceps Walsh. Akron, Ohio, 

 September 26, 1897 ; J. S. Hiue, collector. Ohio State University. 



Fig. 19. — Same of Gomphus scudderi Selys. Northeast Carry, 

 Maine, August 29, 1899 ; F. L. Harvey, collector. Ohio State 

 University. 



EXPLANATION OF PLATE IX. 



Fig. 20. — Gomphus plagiatns Selys. Accessory genitalia of sec- 

 ond abdominal segment of male in detail. Right side, seen in pro- 

 file. The penus is partly withdrawn from its sheath. 



Fig. 21. — Profile view of the male abdominal appeuda,ges of 

 Gomphus amnicola Walsh. Galina, Illinois; Beau, collector. M. 

 C. Z. 



Fig. 22. — Same of Gompkus spiniceps Walsh. Same as Fig. 12. 



Fig. 28. — Same of Gomphus spiniceps Walsh. Quiver Creek, 

 Havaua, Illinois, June 23, 1896 (type of Stylurus segregans Need- 

 ham) ; Needham and Hart, collectors. Professor Needham. 



Fig. 24. — Same of Gomphus plagiatus Selys. Same as Fig. 14. 



Fig. 25.-^Same of Gomp)hus notatus Rambur. Same as Fig. 13. 



Fig. 26. — Same of Gomphus scudderi Selys. Same as Fig. 11. 



Fig. 27. — Same of Gomphus notatus Rambur. One of the types 

 of G. fluvialis Walsh ; Rock Island, Illinois. Type 1009, U. S. 

 Nat. Mus. 



Fig. 28. — Vulvar lamina of Gomphus notatus Rambur. Same as 

 Fig. 25. 



Fig. 29. — Same of Gomphus spiniceps Walsh. Same as Fig. 24. 



Fig. 30. — Same of Gomphus plagiatus Selys. Same as Fig. 27. 



Fig. 31. — Same of Gomphus amnicola Walsh. Rock Island, Illi- 

 nois. M. C. Z. 



Fig. 32. — Same of Gomphus scudderi Selys. Same as Fig. 23. 



TRANS. AM. ENT. SOC, XXVII. (28) MAY, 1901. 



