120 PEOCEEDINGS OF THE NATIONAL MUSEUM vol.68 



turning brown in July, containing pupae at Evanston August 1 

 and 12 and adults on September 20. These adults remain in the 

 galls over winter, emerging in the spring. 



AYLAX GILLETTEI (Kieffer) 



This species produces no visible gall but forms cells in the pith 

 of stems of the compass plants, Silphiuni laciniatum and terehinthi' 

 naceuin. From old dead stems collected at Evanston, 111., in spring 

 of 1912 flies of this and the following species emerged May 15, 30, 

 June 11, 15, 17,22,24, 1912. 



AYLAX RUFUS (Gillette) 



Reared at Evanston, 111., together with above species from stems 

 of compass plant. 



AYLAX HYPOCHOERmiS (Kieffer) 



Early in 1920 A. C. Burrill collected galls on the introduced 

 European plant known locally as the false dandelion (Ilypochoeris 

 radicata Linnaeus) at Albany, Oreg., and sent some to the Bureau of 

 Entomology and some to William Beutenmueller who reared adults 

 in large numbers April 15 to May 15 and was the first to suspect 

 that it was the work of a European cynipid introduced along with 

 the plant. He sent galls and adults to the writer who has in turn 

 submitted them to Prof. J. S. Tavares in Spain for direct compari- 

 son with European material. Doctor Tavares writes that "it is 

 without doubt the European species. The gall is also the same." 

 He sent specimens he had reared in Spain for the Museum collec- 

 tion. Prof. C. Houard, of Strassburg, to whom galls were sub- 

 mitted confirms this determination. This adds another to the small 

 list of gall-making Cynipidae common to Europe and America — 

 ail on introduced European plants. 



In the month of June 1922 the writer saw the galls growing at 

 the following localities in Oregon : Cottage Grove, Walker, Creswell, 

 Eugene, Corvallis, Albany, Jefferson, Salem, Brooks, Woodburn, 

 Hubbard, Aurora, Barlow, Canby, New Era, Oregon City, Portland, 

 Newberg, McMinnville, Sheridan, Willamina, Grande Ronde, Goble, 

 and Troutdale. The plant without any galls on it was noted along 

 the Columbia highway as far east as The Dalles, and as far south 

 along Pacific highway as Grants Pass but not on road from Medford 

 to Crater Lake, and not on road from Grants Pass to Holland. In 

 Washington the plants are very common about Seattle and on road 

 from Tacoma to Ashford but no galls were seen. Thus the cynipid 

 has not kept up with the spread of the plant but wherever it does 

 occur its galls are helping to check the plant by stunting the growth 

 of the flower stalks. 



