ART. 10 GALL-INHABITING CYNIPID WASPS WELD 3 



the ground in the fall especial care must be taken that no galls of 

 other kinds are included in the cages. 



For a number of years the writer lived at Evanston, 111., and 

 collected galls either within the city limits or along the north branch 

 of the Chicago River 4 miles west and along the " north shore " 

 as far north as Waukegan with occasional trips to the sand dune 

 area at the southern end of the lake in Indiana and less frequent 

 ones to the general region of the " sag " southwest of Chicago. In 

 this " Chicago area " the writer found a total of 124 species of 

 gall-making Cynipida3 of which 10 are here described as new. In 

 addition he has field notes on some 30 other galls from this area 

 either not determined or not reared and hence not otherwise here 

 mentioned. Further collecting will no doubt yield still other species, 

 for during the last j^ear or two of residence there it was no imusual 

 experience to find galls that 3'ears of previous collecting had never 

 discovered. Moreover, collecting on tlu-ee of the nine oaks in the 

 region was very fragmentarj^, these being seen hardly more than 

 once or twice a year. Strangely enough, Diastro'plius smUacis Ash- 

 mead, described from the Chicago area as producing a gall on 

 Smilax^ the writer has never been able to find although he has 

 looked for it for years. The oak openings at the edge of the prairie 

 now transformed into the suburbs of a densely populated metropoli- 

 tan district would not be suggested as an ideal region for Cynipid 

 collecting and yet it will be interesting to compare its 125 species 

 with the few published local lists available. In 1904 Beutenmueller 

 listed 46 of the more conspicuous Cynipid galls in the vicinity of 

 New York City. Stebbins in 1910 listed 66 from Springfield, Mass. 

 Sixty-four are known for the Toronto area. 



To make available to students the writer's experience with those 

 species of the Chicago area which have either been reared or are 

 felt to be determined with some certainty these field notes are pre- 

 pared. Some species of the Chicago area producing galls on roots 

 or in acorns were discussed in previous papers and are not included 

 in the present one. To these are added selected species from other 

 localities in cases where sufficient material was at hand for descrip- 

 tion or the writer felt he was able to make some contribution to the 

 imowledge of the species by indicating date of emergence, supplying 

 a host record, or adding additional hosts, or supplementing the pub- 

 lished data of geographical distribution. 



Many years ago Dr. William Brodie gave his large collection of 

 insects reared from galls to the United States National Museum. 

 It occupies 22 museum drawers. Each specimen bears a field note 

 number but the notebook which would have interpreted these 

 numbers was long supposed to have been lost. However, in the 



