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Indiana University Studies 



sex to either form definitely except when they were cut from 

 the galls. Of a total of 185 adults bred from both forms, 94, 

 or just about one-half were males. Most of the adults had 

 not emerged on April 22. 



Diplolepis tuberculatrix variety coloradensis 

 form subcoloradensis, new form 



FEMALE. — Differs from form coloradensis only in being generally 

 black; sometimes with some rufous, especially from the base of the 

 antennae to the mouth, and about the ocelli, on the first three segments 

 of the antennae, on the smooth area of the mesopleuras, and centrally on 

 the scutellum; abdomen often with a rufous tinge. 



MALE. — Quite identical with the male of form coloradensis. 



GALL. — Quite identical with the gall of form coloradensis. 



RANGE. — Colorado: Glenwood Springs. 



TYPES. — 29 females, 4 males, 4 galls. Holotype female, paratype 

 adults, and gall at The American Museum of Natural History; paratype 

 adults and galls at Stanford University, the U.S. National Museum, and 

 with the author. Labelled Glenwood Springs, Colorado; April 22, 1920; 

 Kinsey collector. 



This black form and the red form of coloradensis are 

 identical in structure, and the galls, an indication of the insect 

 physiology, are quite the same. There can be no doubt that 

 the two represent a single variety. Of 91 females obtained 

 from Glenwood Springs, 29 are mostly black. These indi- 

 viduals are usually entirely black altho we obtained several 

 degrees of intermediates between rufous and black. Up to 

 date we have obtained only red or only black insects from a 

 single gall. We have obtained both sexes of the black form, 

 and presumably both sexes of the red form. It is to be noted 

 that black is the color of the males of all varieties of the 

 species, being therefore normally connected with sex inheri- 

 tance. Reproduction in the genus may be from fertilized eggs 

 or parthenogenetically. These facts may be concerned with 

 the occurrence of the black form. We are instituting further 

 investigations with this material to try to determine what 

 peculiar heredity phenomena may be concerned here. Black 

 females occur occasionally in several other varieties of this 

 species, tho not as abundantly as we have found it in 

 coloradensis. We find black individuals in variety rnelanderi 

 and in calif ornica, tho all degrees of melanism are to be 

 found with the latter variety, and the normal female there 

 contains much black ; tiimida is a black form of a Utah species. 



