THE LARCH WORM. 887 



down on the side, while the black spines on the abdominal segments are distinct and 

 arranged as in the full-fed worm. Length, 12'"™. 



Larva of fourth and last stage {P\. IX, Fig. lb). Length at first, 14-16'"'". Bodj- 

 with three pairs of black thoracic and seven pairs of abdominal legs, the color of the 

 under side of the body. (The larva may be distinguished from Lophyrus worms by 

 having one pair less of abdominal legs, the latter having eight pairs.) Body rather 

 long and slender; less plump than in Lophyrus abietis. Head round, jet black (it is 

 usually reddish in Lophyrus); seen from in front, legularly circular, mandibles 

 4-toothed ; maxilhe 4-jointed, the joints longer than in Lophyrus; the mala or inner- 

 most lobe broiid and large at the end, with about ten stift'long setje (in Lophyrus the 

 mala is much smaller, with only three very short setae or stiff spines). The body is 

 of a peculiar glaucous-green color, like that of the under side of the leaves ; the glau- 

 cous-green dorsal region is plainly separated from the paler underside of the body by 

 a definite line. There are no lateral stripes or spots. The first three (thoracic) seg- 

 ments behind the head are plaiu, with no minute warts; but around each abdominal 

 segment except the last run two parallel double rows of minute dark dots or warts. 



The worm is at once distinguished from any other saw-fly larvje, on pines, spruce, 

 and firs, by its larger size, its color, and by its jet-black head and its seven pairs of 

 abdominal legs. 



Cocoon. — Larger an I darker than that of Lophyrus abietis. Length, lO'"'^^ ; diam- 

 eter, 5""". 



The imago or saw-fly (5 females). — A very large, thick-bodied, black species, with 

 abdominal segments 2 to 5, and part of the sixth, bright resin-red. 



Head black; maxillary and labial palpi pale whitish flesh-color. Antennae tapering 

 to the end, black, 9-jointed; the scape with two small short joints, the second shorter 

 than the first ; the flagellum 7-jointed, the second joint considerably shorter than the 

 first, and slightly longer than the third ; the two terminal joints of equal length and 

 slightly paler than the rest of the autennie. The clypeus and especially the labrum 

 covered with white, stiff, short hairs, as also the genae in front. Head and thorax 

 uniformly black, under the triplet seen to be pilose. Basal segment of the abdomen 

 black, segments 2 to 5 bright resinous red, including the basal third of the 6th, this 

 segment beneath being entirely red. 



First and second pair of legs, including the trochanters, pale flesh color, the femora, 

 however, somewhat reddish and tipped at the distal end above with black ; the third 

 pair of femora red, like the abdomen, black at tip ; tibiae pale, black on the outer 

 third; tarsi black, the under spines pale, including the base of the claws. End of 

 abdomen and ovipositor black. Wings with the costa as far as the stigma reddish ; 

 stigma and veins black. Only three subcostal cells, the basal squarish one not being 

 completed, a short obsolete vein projecting from near the stigma. 



Length of body, 11'"'"; of autennae, 6.5'""^; of forewing, 9'"'" ; expanse of wings, 20- 

 2imm_ One specimen considerably smaller than the others. 



Remedies. — It is obvious that iu swamps in the remoter parts of the 

 country these worms cau uot be subdued 5 they will run their course 

 for a term of years. To prevent their killing shade trees, particularly^ 

 small ones, jarring the trees will prove a good remedy, the worms once 

 shaken oft' the tree cau not ascend the trunk, as they do not, like canker 

 worms, climb trees or let themselves down by a thread. Small trees 

 may also be showered with solutions of Paris green, or the various 

 fluid insecticides recommended in the recent reports of the Entomolo- 

 gist of the Department of Agriculture and in the Introduction to this 

 report. 



Parasites. — A number of cocoons sent us in 1882 by Mr. Atkins were 



