72 ENTOMOLOGICAL NEWS. [March, 



G. fraternus 9 Walsh, Proc. A. N. S. Phila. 1862, p. 393 (compare 

 Proc. Ent. Soc. Phila., ii, p. 239. 1863). 



G. consobrinus VJaXsh. Proc. Ent. Soc. Phila., ii, p. 242. 1863. 

 G. consobrinus Selys, Bull. Acad. Belg. (2), xxviii, p. 178. 1869. 



(The remark concerning the vulvar lamina "les pointes divari- 

 quees a angle droit " may refer to the divergence between the inner 

 (mesal) margins of the two lobes). 



I have studied the following material : 4^29 Havana, 

 Illinois, June, 1896 and July 9, 10, 1897 ; 2 9 Illinois Jime 29, 

 1895 and 1896; I 9 Greenwood, Nebraska; i 9 Texas. 



De vSelys, /. c, 1878, gave the following distribution for this 

 species : New Mexico, Texas, Nebraska, Illinois. 



Gomphus crassns Hagen, 



G. crassus Hagen, Bull. Acad. Belg. (2), xlvi, p. 453, 1878. 



G. crassus Williamson, 24th Rep. State Geol. Indiana, p. 288. 1900. 



G. fraternus var. Walshii Kellicott, Jour. Cincin. Soc. Nat. Hist., 

 xviii, p. 107. 1896. 



G. externus Kellicott, Dragonflies of Ohio, p. 60, 1899. 



G. externus Williamson, 24th Rep. State Geol. Indiana, p. 289, 1900, 

 PI. vi, figs. 2, 10, 31.* 



My present material of crassus has been : 1 2 <? Georgeville, 

 Ohio, June 4, 1899 ; 6 <? 3 9 Columbus, Ohio, May 20 to 

 June I, 1895-6-7-9; 2 $ Bluff ton, Wabash River, Indiana, 

 June 22, 1898, Hagen's type came from Kentucky. 



CONCLUSIONS. 

 From the preceding data it appears, /b;' these three species : 



1. That the chief specific character {i. e. the least variable 

 difference between these three .species) is to be found in the 

 shape of the superior appendages of the males. 



2. That every female character, and every character common 

 to both sexes, by which these species are distinguished from 

 each other, is more variable than are the superior appendages 

 of the males. 



3. Walsh's remark t that the Illinois .species of Gomphus 

 seem to have the appendages of the males ' ' nearly as uniform 

 as a set of castings from the same foundry and the same 



* G. cornutus Tough, Occas. Mem. Chicago Ent. Soc, i, p. 17, 1900, 

 does not belong to any of these three species, and his suggestion, p. 18, 

 that it may be the ^ of crassus is not realized. 



t Proc. Ent. Soc. Phila, ii, p. 239, 1863. 



