94 EXTOMOLOOTCAL SOCTETY. 



ters it emerges early in the spring, about the time of the opening of the buds of the 

 currant and gooseberry. Last spring they appeared in unusual numbers, and during the 

 warm parts of the day might be seen in swarms about the bushes. 



In appearance this saw-fly is a little smaller than the common house- fly, and has 

 a yellow body. The male is considerably smaller than the female and is somewhat darker 

 in color. During bright, warm days they are very active, but early in the morning or when 

 the weather is cool and cloudy they are sluggish and may be easily captured. 



Saw-flies are so called because of the saw-like ovipositors of the females. Speaking 

 of these, Prof. Comstock says, " This is at least one instance of where the female wielding 

 of a saw is done most skilfully, for the female saw-fly uses these nice tools in a very efficient 

 manner, to make slits in the leaves and stems of plants in which she places her eggs." The 

 eggs are deposited, from 20 to 40 in number, upon the back of the ribs and veins of the leaf, 

 usually upon the lower leaves of the bushes (Fig. 62) They hatch in about ten days and 

 the young larTte begin to feed at once upon the tender leaves. They grow rapidly, and if 

 unchecked will in a short time entirely strip the bushes of foliage. In the course of about 

 three weeks, the larva? become full grown (see Fig. 10), when they leave the bushes, spin 

 small papery cocoons, and enter the pupa or resting state. From these the adult saw-flies 

 emerge in a short time, and a second brood of lsrvre follow, which strip the bushes again 

 the latter part of summer. 



This is probably one of the easiest insects to hold in check, as it feeds upon bushes that 

 are easily got at, and it is readily destroyed by stomach poisons, such as Paris green or 

 hellebore. The most important points in fighting it are to begin early, as the young larvse 

 are usually well at work by the time the leaves are full grown, and to force the spray up 

 from the under side of the bushes so that it will reach ihe lower leaves where the caterpil- 

 lars begin operations. 



2. The Larch Saw-Fly {Nemdtus Erichsonii), On the 24th of June last, my 

 attention was directed to the scorched appearance of the foliage on the clump of 

 European larches in the field in front of the College. Upon going to examine them 

 closely, I found that they had been almost entirely stripped of their needles by some 

 kind of insect. Upon further investigation I found one or two small trees on the 

 west side of the clump upon which a few of the larvte were still at work. It was a 

 smooth, glaucous green worm which I had never seen before, but from certain char- 

 acteristics, such as the seven pairs of prolegs and the curling under erf the last seg- 

 ments of the body, I recognized it at once, as the larva of some species of saw-fly. 

 Upon consulting Packard's excellent report on "Forest Insects" 1 found it fully des- 

 cribed as the Larch Saw-fly {Nematus Ericlisonii), a new and much-dreaded enemy in 

 the larch and tamarack forests. 



Like the Currant Saw-fly, it is supposed to have been imported from Europe. 

 The first notice of it on this continent was in 1881 by Dr: Hagen upon specimens 

 found in Massachusetts. Two or three years later it was found in vast numbers in 

 Maine, New Hampshire and other New England States, where it had stripped all the 

 tamarack forests. In the report of the Ontario Entomological Society for 1885, Prof. 

 Fletcher of Ottawa gives an excellent account of its life history, and of the devasta- 

 tion it had made in the tamarack swamps of Quebec and the Maritime Provinces. 



It was then noted that the most western point that it had at that time reached 

 was about Casselman, on the Canada Atlantic, about 30 miles east of Ottawa. Its 

 appearance at Guelph last June would indicate that it had made considerable progress 

 westward. In my travels over the Province last summer, I was particular to watch 

 for indications of its presence, and I noticed from the scorched appearance of the 

 tree tops, thatjit had stripped the tamaracks in many places between here and Walker- 

 ton, and that in the large tamarack swamp south of Bradford the trees in July were as 

 bare as if a forest fire had swept through them. 



The adult insect is a handsome saw-fly, somewhat resembling the Currant Saw-fl y 

 but is a little larger and darker colored, being mostly black with an orange band around 

 the middle of the abdomen. The female deposits her eggs in incisions made in the young 



