91 



imbedded in it the larva of the above species. By means of a hot iron I separated 

 a cube of ice with the inclosed larva, and took it to my office. The caterpillar 

 was entirely and solidly inclosed by the ice ; no air-spaces could be detected 

 among the hair. How long the caterpillar had been inclosed I could not say. 

 Left the cube of ice in front of my window, where the temperature sunk for two 

 days to 11° below zero. Later the weather moderated, and during the day a little 

 ice would melt near the caterpillar, but never exposing it to the air. After being 

 inclosed for fourteen days, I carefully melted the ice and removed the caterpillar 

 to a piece of blotting paper. In less than thirty minutes the larva was crawling 

 about, not injured in the least. Yet, to escape further cKperimentation, it has 

 shown good sense and spun up, and transformed into a pupa, healthy to all 

 appearances." 



Saw-fly Borer ly Wheat. — Prof. J. H. Comstock, Entomologist, Cornell 

 University, Ithaca, N. Y., describes a new saw-fly working in wheat, known as 

 Oephus pygmaeus, order Hymenoptera, of the family Tenthredinidae as follows 



An insect destructive to wheat, but previously unknown in this country, has 

 appeared in considerable numbers on the Cornell University farm. I do not 

 know of its occurrence anywhere else in this State ; but as it is extremely abun- 

 dant here, it is doubtless spread over a considerable area. It was first observed 

 in this locality two years ago by one of our students, the late Mr. S. H. Grossman 

 while makinof an investiofation of wheat insects. Mr. Crossman's studies, how- 

 ever, were sadly terminated before he had carried his investigations of this 

 species very far ; and it has fallen to me to continue the work begun by him. 



On examining the stalks of wheat at harvest time by splitting them through- 

 out their length, it was found that some of them had been tunnelled by an insect 

 larva. This larva had eaten a passage through each of the joints so that it could 

 pass freely from one end of the cavity of the straw to the other. In addition to 

 tunnelling the joints they had also fed more or less on the inner surface of the 

 straw between the joints ; and, scattered throughout the entire length of the cav- 

 ity of the straw, except the smaller part near the head, were to be seen yellowish 

 particles, the excrement of the insect. 



If infested straws be examined a week or ten days before the ripening of the 

 wheat, the cause of this injury can be found at work within them. It is at that 

 time a yellowish, milky- white worm* varying in size from 1-5 inch (5 mm.) to J 

 inch (12 mm.) in length. The smaller ones may not have bored through a single 

 joint ; while the larger ones will have tunnelled all of them, except, perhaps, the 

 one next to the crround. 



As the grain becomes ripe the larva works its way towards the ground, and 

 at the time of the harvest the greater number of them have penetrated to the root. 

 Here in the lowest part of the cavity of the straw they make preparations for 

 passing the winter, and even for their escape from the straw the following year. 

 This last is done by cutting the straw circularly on the inside, nearly severing it 

 a short distance, varying from one-half inch to one inch from the ground. If the 

 wheat were growing wild, the winter winds would cause the stalk to break off at 

 this point, and thus the insect after it had reached the adult stage in the following 

 year could easily escape ; while but for this cut, it would be very liable to be 

 imprisoned within the straw. But under ordinary circumstances the straw is 

 cut by the reaper before it is broken "off at this point, and consequently that 

 breaking off does not occur. If, however, there is a strong wind just before the 

 harvest and after the straws have been cut in this manner by the insects, they 



