97 



scription. Brodie's description is as follows : "Tlie galls appear like swell- 

 ings on the flowering branches of Monanla flstulosa. from 10 to 22 mm. 

 long, usually a little curved and retaining the quadranglar form of the 

 brancli. The average of the side of the square of 20 of the largest was 

 3 mm., and of the branches below the galls 1.5 mm." 



"This gall is usually found on plants growing in open woods, it is 

 very rare on robust plants irrowing on exposed situations." 



"The walls of the gall are liard and woody but thin; tlie interior is 

 a soft, jiith-like substance, through which the larva tunnels freely, and 

 on which it feeds.'" 



Cecidomyia eregerontis Brodie ( ?) 

 IJiplosis eregcroni — 



Brodie, Biol. Rev. of Ont. Xo\. I. Xo. 1. ]\ 13. 

 Cccidom yia eregerontis — 



Aldrich, Cat. of N. A. Diptera. 1005. p. 102. 



This gall was described by Brodie as follows: "N'ariously situated 

 from base of stem to ti])S of branches of flowering panicle; galls irregu- 

 larly cylindrical, tajiering at both ends, spindle-form, those on the branches 

 more or less .spherical ; from 1 to 15 galls on a plant, seldom more than 

 10; found usually on dinunutive plants such as grow on wet, sandy places 

 or on high dry banks." 



"As yet I have not found these galls on robust plants." 



"The galls appear like swellings of the stem or branches, uniform in 

 color with the plant, the surface with feint longitudinal lines, slightly ele- 

 vated ridges and ragged transverse elevations, resembling leaf scars." 



So far as I am able to determine this gall has not been reported since 

 the original description, but during the past summer I collected what ap- 

 pears to be the same gall at Lewes, Delaware. All collections to date 

 have been on Erigeron canadenfie. 



TKYl^ETIDAE. 



Oedaspis gibba Loew. 

 Trypeta gibha— 



Osten Sacken, Psyche. Vol. III. No. 72. 1880. p. 53 

 [7—18192] 



