210 IITMENOPTERA. 



In this connection he refers to the discovery of Clans, in 

 1867, of several males of Psyche helix, -which had been snp- 

 posed to be parthenogenons, thousands of specimens having 

 been bred by Siebold, all of which were females. 



Baron Osten Sacken (in the Proceedings of the Entomol- 

 ogical Society of Philadelphia, vol. 1, p. 50) sa3S that "a 

 strong proof in confirmation of my assertion is, that in 

 those genera, the males of Avhich are known, both sexes 

 are obtained from galls in almost equal numbers ; even 

 the males, not unfrequently, predominate in number (see 

 Hartig, 1. c. iv, 399). Now the gall-flies, reared by me 

 from the oak-apple, were all females. Dr. Fitch, also, had 

 only females ; and Mr. B. D. Walsh, at Rock Island, 

 Illinois, reared (from oak-apples of a different kind) from 

 thirty-live to forty females, without a single male. This 

 leads to the conclusion that the Cynipes of the oak-apples 

 belong to the genera hitherto supposed to be agamons." 



For an account of the habits and many other interesting 

 points in the biolog}"^ of these interesting insects, Ave further 

 quote Baron Osten Sacken. ' ' Most of the gall-flies alwaj's attack 

 the came kind of oak; thus, the gall of C. seminator Han-is. 

 is ahvays found on the white oalc ; C. tubicola Osten Sacken on 

 the poGt oak, etc. Still, some galls of the same form occur on 

 different oaks ; a gall closely resembling that of C. quercus- 

 glohulus Fitch, of the white oak, occurs also ou the post oak, 

 and the swamp chestnut oak ; a gall Aery similar to the com- 

 mon oak-apple of the red oak occurs on the bhick-jLack oak, etc. 

 Are such galls identical, that is, are they produced by a gall-fly 

 of the same kind? I have not been able to investigate this 

 question sufficiently. Again, if the same gall-fly attacks dif- 

 ferent oaks, may it not, in some cases, produce a slightly differ- 

 ent gall ? It Avill be seen below, that C. quercus-futilis, from a. 

 leaf-gall on the Avhite oak, is A'cry like C. qxtercns-papiUata from 

 a leaf-gall on the swamp-chestnut oak. I could not perceive 

 any diuerence, except a very slight one in the coloring of the 

 feet. Both gall-flies may belong to the same species, and 

 although the galls are somcAvhat different, they are in some 

 respects analogous, and might be the produce of the same gall- 

 fly on two difierent trees. 



