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 raptures by himself, as well as valuable 
notes on species we had sent him for examination. The 
Membracidae have mostly been determined by 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 
