8 NEW YORK STATE MUSEUM 



blocks of forest and proving injurious over hundreds of acres. The 

 snow-white Hnden moth, Ennomos subsignarius Hiibn. 

 was extraordinarily abundant on beech trees in the Catskills, de- 

 foliating large areas in and about the township of Hardenburg. 

 Both of these outbreaks are unusual, as neither of these species has 

 been injurious in New York State for some years. Detailed ac- 

 counts of these insects have been prepared and are given in subse- 

 quent pages. 



Aquatic insects. The studies of our fresh-water insects have 

 been continued. Prof. James G. Needham has completed his report 

 on the work done at Old Forge, N. Y. in 1905, and the results 

 are given in appendix C. This report is particularly valuable on 

 account of the new methods employed in ecological work of this 

 character and because of its additions to our knowledge of the 

 food of fish. There are in addition biological notes on a number 

 of aquatic forms. This report also embodies a valuable addition to 

 our knowledge of the midges (Chironomidae) by Dr Johannsen. 

 Furthermore, the large amount of new matter, relating to stone 

 flies (Plecoptera) and the caddis flies (Trichoptera), acquired at 

 this time by Messrs Needham and Betten, has been withheld for 

 monographic accounts of these groups. Professor Needham's 

 studies of the stone flies are nearly completed and they will prove 

 an extremely valuable addition to our knowledge of this group. 

 Dr Betten, who has been investigating the caddis flies for the past 

 six years, has nearly completed his report upon these forms. The 

 investigations of these two gentlemen, when published, will con- 

 stitute in connection with bulletins previously issued by this ofiice, 

 an unrivaled contribution to our knowledge of the aquatic insects 

 of the State, a group which is of great economic importance owing 

 to its value as fish food. 



Gall midges. This group comprises among its members, sev- 

 eral insects of prime economic importance, such as the Hessian 

 fly, the wheat midge, pear midge and some other destructive forms. 

 Furthermore, there is every probability that some other of our 

 native species may become destructive in the near future. Our in- 

 vestigations have already disclosed hitherto unsuspected injuries by 

 members of this group. We have succeeded in identifying several 

 European forms not previously known to occur in this country. 

 During the season we succeeded in rearing probably well over 100 

 species, a considerable number of them proving to have been un- 

 described. Appendix D contains descriptions of over 50 new 



