author's name and the number of the paper only being given 

 in the body of the list. 



The determinations of specimens have been made by 

 specialists in the different groups, the authors doing a large 

 proportion of the systematic work on the Homoptera. It is 

 hoped that this work will be found reasonably free from 

 errors. In the preparation of the list we have been greatly 

 aided by Mr. E. P. Van Duzee, who has made a large number 

 of determinations for us, has made many helpful sugges- 

 tions, and loaned us papers from his private library. We are 

 under very special obligations to Dr. P. R. Uhler of Baltimore 

 who has worked over our entire collection of Heteroptera 

 and described the forty-seven new species and five new 

 genera here published. Professor T. D. A. Cockerell of New 

 Mexico, has determined nearly all our Coccidae and sent us 

 many records of captures by himself, as well as valuable 

 notes on species we had sent him for examination. The 

 Membracidae have mostly been determined l^y Dr. Goding 

 of Rutland, Illinois, and the Psyllidae by Dr. Riley. Pro- 

 fessor Herbert Osborn of Iowa, also determined several 

 species in the early part of the work. Mr. J. H. Cowen, 

 a post graduate student, has done the work on the 

 Aphididae, a large proportion of which he collected himself. 

 Prof. W. A. Snow, of Kansas, has sent us a list of the Colorado 

 Hemiptera in the Kansas University collection, which has 

 added several species and many records to our list. Dr. Riley 

 sent us a similar list from the United States National 

 Museum. 



It will be noticed that a great many species in the list, and 

 especially of those that are new, are from mountainous 

 localities where but little or no collecting had been previously 

 done. All portions of the state still promise rich harvests 

 to the collector, and especially those parts which have never 

 yet been visited by "bug-net" and cyanide bottle. The list 

 of new species here presented, although large, must be 

 small compared with the forms yet unknown. 



Work of a nature similar to this is being done in all 

 orders. In view of this fact we most earnestly solicit 

 correspondence from any quarter relative to the Colorado 



