FIELD BOOK OF INSECTS. 



Plate CI: Eurosta solidaginis (Fig. 10 

 Goldenrod 



emerged), pithy inside with a rounded cell in the center on 

 the main stalk; Rhopalomyia solidaginis (Fig. n), caused 

 by the arrest of stalk; (Edaspis polita (Fig. 12), caused by 

 the arrest of side branches. Lasioptera solidaginis makes 

 a gall much like that of Eurosta. Galls made by two 

 genera of moths are often confused with these but, if the 

 larvae are present, one can at least determine whether or 

 not they are Lepidopterous ; to mention two species: the 

 gall of Gnorimoschema gallasolidaginis is about the size of 

 Eurosta but is more tapering (adults emerge in September 

 and hibernate), that of Eucosma scudderiana is merely an 

 elongate thickening of the stem near the flower head 

 (adults are found from June to August, larvae or pupae 

 hibernating). The aerial gall of Rhopalomyia hirtipes is 

 a large swelling of a bud "resembling a dried prune in 

 texture; hard center"; it also makes a subterranean root- 

 stalk swelling. R. fusiformia causes a ribbed, elongate 

 structure, about a quarter of an inch in length, which 

 occurs singly or in masses on the stem or foliage. Species 

 of Asteromyia live mostly in galls, which are apparently 

 affected with fungus; carbonifera causes a black blister 

 and rostz, a rosy one; similar galls occur also on asters. 

 About 1 50 kinds of galls have been recorded from American 

 Compositae. 



Plate CI, Fig. 9: Contarinia canadensis, 

 succulent, pale green and sometimes tinged 

 with red, formed in May or June. Eriophyes fraxiniflora 

 deforms the catkins ; and E. fraxini makes numerous galls 

 on a single leaf, wart-like, subdivided by irregular, hairy 

 curtains within. Dasyneura tumidosa causes a gall much 

 like pellex but on the base of the midrib and apical part 

 of the petiole. 



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