MAPLE BORERS. 383 



4. Oryssus sai/i Westwood. 



This interesting saw-fly has been proved by Mr. W. H. Harrington 

 to breed in the wood of old dead sugar maples, while he thinks that 

 it may also infest the willow, and possibly a variety of trees, but 

 whether it feeds on the wood or is parasitic has yet to be determined. 

 The perfect insect in Canada appears in June. It is very lively in its 

 movements and might be mistaken for a moth. (Can. Ent., xix, p. 8L, 

 1887.) 



The saiv-fly. — Body stout, black, cylindrical. Length about one-half an inch. 

 Face very coarsely punctured, sometimes with a short white line on each side ; the 

 vertex prominent, and the lower ocellus surrounded with conspicuous tubercles ; 

 eyes moderately large. The antennae are peculiar : In the male they have eleven 

 joints, the third slightly longer and four to eleven subequal : in tbe female they have, 

 however, only ten joints, of which 4, 5, and 10 are very short ; in both sexes they are 

 touched with white near the middle. The wings are hyaliue, with a broad, smoky 

 band commencing near the stigma, and extending almost to the tips. The legs have 

 a spot on the tip of the femora, and a line on the tibia without white. In the 

 female the anterior pair is swollen, the tibiye crooked, and the tarsi with only three 

 joints. The abdomen has the basal segment very coarsely punctured, or scabrous; 

 the remaining ones polished, shining, varying in color as previously mentioned. 



The ovipositor is of special interest, as it differs remarkably from those of the 

 other Uroceridae. Usually it is not visible, as when retracted the tip is concealed in , 

 a deep cleft in the terminal segments. It has the appearance, as stated by Norton, of 

 springing from the last segment, but it is evidently attached much nearer the base 

 of the abdomen, and is protruded from beneath a small ventral scale, whicli is 

 apparentlj"^ a portion of the fifth segment. It is very slender, hair-like, and nearly 

 twice as long as the insect, and must consequently be coiled within tbe abdomen in 

 a manner somewhat similar to that of Ibalia. Norton says it is ordinarily concealed 

 in a channel beneath the abdomen ; Brull^, and other authors, as rolled spirally 

 within it. (Can. Ent. xix, May, 1887, p. 85.)* 



5. Oryssus terminaUs Newman- 

 Mr. Harrington records having taken specimens, "both in the act of 

 emerging from the trunk of a dead maple, and in the act of ovipositing 

 therein." It appears in June. 



*Ibalia macuUpennis Hald. " This curious species belongs to the family Cynipidae, 

 or gall-forming hymenoptera, and is much larger than any of our other species. It is 

 nearly three-quarters of an inch in length and the wings expand about an inch. The 

 head and thorax are stont, but the abdomen is compressed laterally until it is very 

 thin, and has the shape almost of a knife-blade. Tbe ovipositor is very long and 

 slender, and when not in use is retracted and coiled up in the abdomen. The insects 

 are rare, and have only recently been recorded (by Provancher) as occurring in Can- 

 ada. I find both sexes upon old trees in June, and have found the female oviposit- 

 ing in the bark. The general color is yellow, with brown spots upon tbe head and 

 thorax, and with black bands upon the abdomen and the legs. It is possible that 

 the larv.-e may be parasitic upon those of one or more of the insects mentioned in 

 this paper." (Harrington, Uep. Ent. Soc. Ontario, 1887, p. 24.) 



