SOME PEMPHIGINiE ATTACKING SPECIES OF 

 POPULUS IN COLORADO. 



By C. P. Gillette. 



Thecahius populimonilis Riley. 



This species was described by Dr. Riley, who recorded it 

 from Greeley, Colorado, and from southern Kansas. He 

 described the alate female of the second generation taken during 

 July, and said that it always occurred solitary in the galls. 

 The description fits the examples that we have taken during 

 the same month. 



Thomas in his Eighth Report as State Entomologist of Illinois, 

 page 205, copies Riley's description, but adds nothing to it. 



Oestland in his Synopsis of the Aphididce of Minnesota, page 

 24; and Packard in his Forest Insects, page 434, list this species. 



Cowen in Bulletin 31, Colorado Experiment Station, page 

 116, listed this species as occurring at Fort Collins and Hotch- 

 kiss in Colorado, the latter place being on the western slope of 

 the Continental Divide. Cowen also stated that only one 

 louse seemed to reside in a gall. 



Hunter lists this species in his AphididcE of North America. 



In the Journal of Econoniic Entomology for 1909, page 356, 

 the writer recorded what seemed to be this species infesting 

 the margins of the leaves of Populus trichocarpa at Portland, 

 Oregon, and observed that there was but a single large louse in 

 each gall, all of which were becoming winged, and that the 

 young of these lice were migrating to the young leaves as soon 

 as born, where they were forming new galls for themselves. 



In 1910, the University of Nebraska published a manu- 

 script on the " Aphididae of Nebraska," which included notes on 

 this family prepared by the lamented Thomas Albert Williams, 

 which again copies the original description and extends the 

 range of this species to Squaw Canon, Sioux County, Nebraska, 

 .and credits Professor Bruner with recording the species in 

 Idaho and Utah.. 



Dr. Edith M. Patch, in Bulletin 213 of the Maine Experi- 

 ment Station (June 1913) has extended the habitat of this 

 insect to the cotton woods of Maine, where she has taken the 

 ^alls and their inmates upon the leaves of Populus balsamifera. 



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