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are very liable to break off ; the lodging of the grain may, therefore, be largely 

 due to the injuries of this insect. In one field just before the harvest I observed 

 a large number of isolated straws lying in a horizontal position ; there was not 

 the general breaking down of the grain characteristic of wind and rain ; but 

 distributed through the grain that was standing there was a large number of 

 isolated straws that were lodged. A careful examination showed that this 

 breaking down of the grain, in 45 per cent, of the cases, was directly due to the 

 injuries of this insect. In many cases the straws had been broken off a consider- 

 able distance above the ground, and before the larva had made the characteristic 

 circular cut near the root. An examination of these straws showed that the 

 larva had eaten all, or nearly all, of the softer inner part of the straw for a short 

 distance, thus making a weak place which was easily broken. As a rule, how- 

 ever, the larva obtains a greater part of its nourishment by tunnelling the joints 

 of the straw and does not eat enough of the straw in any place to cause it to 

 break until it makes the circular cut near the ground described above. 



After the circular cut has been made, the larva fills the cavity of the straw 

 just below it for a short distance with a plug of borings. Between this plug and 

 the lower end of the cavity of the straw there is a place measurmg about one- 

 half inch in length (10 mm. to 15 mm.) It is here that the insect passes the 

 winter. Immediately after cutting the straw and making this plug the larva 

 makes a cocoon by lining the walls of this space with a layer of silk. This layer 

 is thin but very firm and more or less parchment-like ; it can, however, be broken 

 with slight difficulty, being somewhat brittle. 



Within this cocoon, which remains in the stubble after the grain is cut, the 

 insect passes the winter, in the larval state. It changes to a pupa during March 

 or April ; and sometime during the month of May the adult insect appears. 



The exact date of the appearance of the insect depends upon the nature of 

 the weather. This year from pupse collected on the 23rd of April and brought 

 into the Insectary, the adults emerged from the 8th to the 10th of May ; while- 

 the insects left in the fields were ten days later in emerging. 



The adult insect is a four- winged fly belonging to the order Hymenoptera, 

 the order that includes the bees, wasps and ants ; and it is a member of the family 

 Tenthredinidae of this order, a family comprising the insects commonly known 

 as saw-flies. This popular name refers to the fact that in this family the female 

 insects are furnished with a more or less saw-like organ. This arises near the 

 caudal end of the body, and is the ovipositor. By means of it the insects are 

 able to make incisions in the tissues of plants for the reception of their eggs. 



In the Canadian Entomologist, 1890, p. 40, Mr. Harrington records the 

 occurrence of this insect at Ottawa, Ont., and also at Buffalo, N. Y. 



The Habits of a Ground-Hornet. — Stizns speciosus is the largest native 

 ground-hornet, and its formidable appearance and great activity generally secure 

 it undisputed possession of the square rod where it happens to alight. It is from 

 an inch to an inch and one half in length ; the head and thorax are brown and 

 the abdomen is black with six irregular yellow blotches. These markings are 

 discernible as it flies swiftly about its business and give it a particularly tiger 

 like appearance. It seems to be afraid of nothing, and if you walk near its 

 burrow it flies with a menacing buzz in circles about you, and its brown, black 

 and yellow body gleams in the sunlight. 



In constructing its burrows it usually selects a country road side or a dry 

 barren hill, where a freedom from roots makes digging less laborious. 



