798 FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 



fairly bristling with protrudiug pupa skins, are a common sight on trees affected by 

 these insects. The adult insect is large, measuring 9"^"^ (.354 inch) in wing-expanse. 

 The head is blackish, the thorax gray, and the abdomen dark red. The male antenmv 

 are 26-jointed, with alternate singleand double joints, all pediceled; the female, 14- 



Fig. 270. — The pitch inhabiting midge.— After Conistock, 



jointed. The main peculiarity of the adult form is in the remarkable gibbosity of the 

 head, the eyes joining together at the summit and covering nearly the whole head. 

 The wing-venation and other points are shown in the figure. The resin exuding from 

 the wounds in P. inops is perfectly clear, and permits one to count the number of the 

 larvae and to watch their every motion. 



" We have as yet no data upon which to state definitely whether the 

 eggs of the midge are laid upon the uninjured bark, and it is the work 

 of the larv?e in the bark which causes the resin to exude, or whether it 

 is only in resinous exudations, caused by a bruise or by the work of 

 some other insects that the eggs are laid. In the clear lumps on Pinus 

 inops the larvae are always observed with their heads applied to the 

 abraded bark. 



" Somewhat similar, though evidently distinct larv?e were found feed- 

 ing in the resin exuding from the wounds made by the larva of Eetinia 

 comstocMana in the twigs of Pinus rigida. It is probable that they may 

 be OstenSackeu's Cecidomyia pini-inojns, but it is difficult to say posi- 

 tively as his description of this species is so very indefinite." (Comstock.) 



Upon the loblolly pine (P. tceda), however, it is milky, and the presence of the in- 

 sect can not be ascertained without opening the mass. 



We have noticed the work of this gall-fly at Providence, the cast 

 pupa skins being found protruding from the masses of pitch June 28. 

 We have also observed ;t for many years past at Brunswick, Me. 



128. The pitch-pine needle gall fly. 



Diplosis pini-rigidw Packard, 



Shortening and deforming the needles of the pitch pine, in Maine, early in May, 

 orange-colored larva}, which .spin a cocoon toward the end of May ; the fly appearing 

 probably in June, as the second brood of larvoo occur late in September. 



