372 TUB CANADIAN EXTOMOLOOIBT. 



As the botanists are becoming more interested in the study of galls, 

 future lists will, in all probability, contain a closer classification of the 

 host-plants of the various galls. 



In the vicinity of the City of Toronto the galls produced on Solidago 

 plants by Lepidoplera are of frequent occurrence, and the various forms 

 are closely restricted to certain species of host plants. 



In the locality mentioned, the gall produced by the moth Eucosma 

 Scudderiana Clemens, is found abundantly on Solidago Canadensis L., and 

 very seldom on S. serotitia, var. gigantea Gray. 



The moth Gnorimoschema gallitsolidaginis Riley, produces its galls 

 frecpiently on both of these species of Solidago; the galls on the latter host 

 are, however, slightly less numerous. 



The ninth G. asterella Kell., produces galls which are locally 

 abundant on S. latifolia L., but are found very rarely on S. caesia, var. 

 axillaris Cray. 



In the CANADtAN F.NTOMoi.oGiST, Vol. XM, No. 5, p. 157, the late 

 Dr. Hrodie records the notes he has made on the gall produced on 5. 

 caesia. In these occurs the following statement : "There is a suspicion 

 that the S. caesia gall is produced by G. asterella Kell." Profiling by 

 these observations and taking advantage of the fact that the galls were 

 comparatively numerous this season on S. caesia, several of the entire host- 

 plants were removed and placed in vessels of water under bell-jars. A 

 number of the galls produced on 5. lati/olia were taken at the same time. 

 From Aug. 12th to 19th producers were emerging from the galls on both 

 species of plants. Specimens of the moths, bred from each species of 

 plant, were sent to Mr. .\ugust Busck, of the United States National 

 Museum, Washington, D. C, and he has kindly given an authoritative 

 classification of the producers. He stales, "the gall-moths bred from both 

 Stilidago species are without any dispute G. asterella Kell." 



The gall produced on S. caesia is quite unlike the S. lati/olia gall in 

 appearance, but as both galls are merely spindle-shaped enlargements of 

 the stems of the host-plants, this difference in outward form can easily be 

 explained. The glaucous, terete and slender siem of ^S". caesia produces 

 a gall with glaucous epidermis, circular in cross section and gradually 

 tapering towards each end. On the other hand, the smooth, angled and 

 comparatively thick stem of S. lati/olia gives rise to a gall with smooth 

 epidermis, somewhat triangular in cross-section. This gall has also a 

 greater diameter and tapers more abruptly than the 5. caesia gall. 



