27 

 THE SAW-FLIES OF THE PROVINCE OF QUEBEC. 



Rev. Thomas W. Fyles, D.C.Iv., Ottawa. 



Tenthredinina. 



"One sex onl3' bears a weapon 

 Near the tail, beneath the body, 

 Sharply notched and very sawlike, 

 And with this she quickly pierces 

 A young leaf or juicy sucker, 

 And her eggs sedately places 

 In the wound she hascreated; 

 From this saw ^ve call them saw^-flies. 

 Saw-flies or Tenthredinina." 



Newman, THE INSECT HUNTERS, p. 34 



A formidable battalion in the host of insects injurious to vegetation 

 is presented by the Tenthredinina which are commonly known as Saw- 

 flies. They derive their familiar name from a remarkable provision, found 

 at the end of the abdomen, in the females of the various species. This 

 consists of a double saw contained in a cleft. The blades of this are 

 placed side by side andi are toothed on the outer edge. They can be pro- 

 truded, and \vorked backward and forward, and w^ithdrawn w^hen not 

 in use. With these instruments the mother fly cuts little slits in the 

 leaves or tender twigs of plants to form receptacles for her eggs. 



One beautiful August day in the year 1897, I was strolling through 

 a grove of aspen poplars on the heights of Ivcvis, when my attention was 

 taken by some streaks of light on tlie underside of a leaf that quivered 

 above me. I found that these streajcs were reflections of the bright sun- 

 shine from the upturned edges of incisions through the epidermis of the 

 leaf. I knew the woundls had been made by a saw-fly which had deposi- 

 ted an egg in each of them. The larvae in breaking away had raised the 

 edges of the wounds, and then had wandered off. I made a search for 

 the stragglers and soon found them. In a number of leaves near by 

 round holes were bitten; and, extended along the edge of each of these was 

 a thread-like larva. The creatures belonged to the species Amauronema- 

 tus luteotergum Norton. 



(For description of the full grown larvae and imagos of these insects 

 see the 28th Annual Report of the Entomological Society of Ontario, 

 page 73 ) . 



The wounds made by some species of saw-flies cause an abnormal 

 growth which takes the form of galls on the food-plants of the species. 

 The rosy, kidney-shaped galls so abundant on the white willow are fam- 



