THE PITCH MIDGE 797 
body of one of the leaf-raining larvae. They are pale milk-white in color, and the 
alimentary canal blackish; they are loug and slender in form. Avery small Ta- 
china fly was also bred, both from the northern and southern specimens. (Comstock 
in Agricultural Report for 1879.) 
We have found at Brunswick, Me., young pitch-pine trees the leaves 
of which had been attacked by this larva; the injury was quite local, 
not general. We found larvae April 4, 1883, on the outside of the leaves 
of P. rigida, on leaves affected last year, boring in the needles near the 
middle. This is the only Tineid recorded, as far as we know, as living on 
the pine, which seems remarkably free from the attacks of this family. 
127. The pitch-inhabiting midge. 
Diplosis resinieola Osten-Sacken. 
Order Diptera ; family Cecidomyid^e. 
Feeding early in May, and again towards the middle of June, in companies of 
thirty or forty, in the pitch exuding from wounds in the bark of the pitch-pine, 
small, slender, footless, orange larvae, changing to two-winged midges or gall-flies 
late in May and the middle of June. (Comstock.) 
The following account of this interesting fly is taken from Professor 
Comstock's Report for 1879: 
In 1868, Mr. Sanborn exhibited before the Boston Society of Natural History speci- 
mens of a " Cecidomyious larva," which he had found feeding in companies of thirty 
or forty in the pitch exuding from wounds in the bark of Pinus rigida. '"'Whether 
they were the prime cause of the injury to the tree was not plainly apparent." (See 
Proceedings Bost. Soc. Nat. Hist., xii, p. 93. ) In the Proceedings of the Entomological 
Society of Philadelphia, 1871, p. 345, Osten-Sacken records the discovery of similar 
larvae in the exuding resin of Pinus inops at Tarrytown, N. Y. These he reared to 
the perfect state, and gave the species the name of Diplosis resinieola. 
Early in May the two-or-three-year-old branches of Pinus inops in the vicinity of 
Washington were observed to be quite extensively infested by these insects, which 
were then in the larva state and actively feeding. They shortly turned to pupae, and 
the first midge emerged May 26. On June 11 larvae of the same species were found 
upon the twigs of Pinus rigida at Ithaca, N. Y. Pupae were also found in the same 
twigs, and June 13 the first midge issued. In February, 1880, I collected specimens 
of similar larvae at Orange Lake, Florida, on twigs of Pinus twda, which, upon the 
appearance of the adults on March 1, were found to be of the same species. 
Fig. 87 (from Comstock) shows well the work of this insect. The lumps of exuding 
resin may contain from two to thirty of the larvae, which, when full-grown, measure 
on an average 6 mm (about one-quarter of an inch) in length. While still feeding they 
are pale-orange in color, but after ceasing they become of a bright orange. The 
spiracles of the anal segment are at the summit of two protruding tubercles, and 
around each is a small whorl of four fleshy papillae. The other spiracles are small 
and black. The larvae are much elongated, and are widest at the 6th segment ; the 
undersides of segments 1 to 7 are furnished each with two transverse rows of short 
black or brown spines, probably for locomotive purposes. While burrowing in the 
bark and resin the anal tubercles are always at the surface. When, however, the 
larva contracts to pupate, the end of the body is drawn in, but an open channel is 
left so that the air has free access. When about to give out the adult, the pupa 
works its way to the surface of the resin and protrudes half its body, so that there is 
no danger of the midge becoming fastened in the sticky gum. Dried lumps of resin, 
