262 



NEW YORK STATE MUSEUM 



Rhopalomyia gnaphalodis Felt 



191 1 Felt, E. P. Econ. Ent. Jour., 4: 484 



This form was reared April 25-29, 19 10 by Prof. T. D. A. Cock- 

 erell, Boulder, Col., from a woolly polythalamous gall on Arte- 

 misia gnaphalodes. 



Gall. An irregular, lobulate, polythalamous swelling 1 cm in 

 diameter and 1.3 cm long. The surface is irregularly wrinkled and 

 thickly clothed with short, white pubescence. 



Exuviae, protruding from a circular exit hole, whitish trans- 

 parent. 



Rhopalomyia pedicellata Felt 



1908 Felt, E. P. N. Y. State Mus. Bui. 124, p. 365, 366 



1909 Ottawa Nat., 22: 248, 249 



1910 Stebbins, F. A. Springf. Mus. Nat, Hist. Bui. 2, p. 53 (Cecidomyia 

 euthamiae Stebbins) 



This species resembles R. fusiformis both in the form of 

 the gall and the general appearance of the adult. The gall, how- 

 ever, is easily distinguished by the long stem or pedicel which is 

 about one-half the length of the deformity. The galls occur on the 

 narrow-leaved solidago, Solidago graminifolia, the ear- 

 lier ones become fully developed about the middle of July and others 

 may be found from that date to the end of the summer. This 

 species is rather common in the vicinity of Albany. 



Gall. The gall is about 2 cm long, the stem being .6 or .7 cm in 

 length, while the slender, enlarged, fusiform portion is 1.3 to 1.4 cm 

 long. The latter is strongly ribbed, deep purplish green at the tip. 

 It frequently arises from the edge of the leaf, occasionally from the 

 flat surface of either the leaf or stem. The interior walls are suc- 

 culent when fresh, becoming mealy after drying. A single whitish 

 larva some 3 mm long occurs in each gall. See New York Museum 

 Bulletin 175, Plate 1, figure 6, for a colored illustration. 



Pig. 71 R hopalomyia pedicellal a; fifth antenna! segment of male, 



enlarged (original) 



