14 B. C. ENTOMOLOGICAL SOCIETY 



NOTES ON THE HYBERNATION OF SOME LARVAE AND 

 THE MOVEMENT OF BOREUS IN THE SNOW 



By J. \Vm. Cockle, Kaslo 



The statement is often made that Snow Fleas, as they are commonly 

 called, come up through the snow. This statement has often struck me 

 as strange and altogether improbable. How could an insect get through 

 several layers of frozen snow, which represent the results of thawing 

 and are generally described as crusts? But like our old friend Mark 

 Twain, "I have watched him." The summary of results follows : 



The actions of the snow insects form a reliable barometer, and as 

 they become readily visible after the first snow has whitened the ground, 

 their observation becomes easy. 



It is well to enumerate the changes that occurred in the temperature 

 in order that we may more readily understand the extreme changes that 

 insects are subjected to in this locality. 



On November 17th, 1916, the winter commenced with a slight fall 

 of snow and sleet, followed the next night by a fall in the temperature 

 to below zero. The temperature gradually rose for the next few days, 

 and then it snowed about six inches. The following morning, when 

 the temperature stood at freezing point, the snow was covered with 

 insect life. Boreus californicus was very numerous, and I also observed 

 five species of spiders, the most plentiful of which is a pale greenish 

 stone colour, having two yellow stripes lengthwise of the abdomen. 

 I may note, in passing, that these spiders have been fairly common on 

 the snow all winter, but the most remarkable thing that came under 

 my observation was the number of noctuid larvae that were out on the 

 surface of the snow, and were in a lively condition. The natural con- 

 clusion was that they had been caught by the early snow and although 

 they had managed to crawl upward through it, away from the frozen 

 ground below, that they would eventually succumb to the cold and find 

 a grave in the snow, but remarkable as it may seem, their appearance 

 later demonstrates that they will live and thrive in the snow. We had 

 a continuance of cold weather and snow up to Christmas. On the 

 night of the 26th December the temperature again fell to below zero, 

 moderating again in a few days, and then another heavy fall of snow 

 (making a total fall to date of 24 inches) with a temperature of 30 

 degrees. Numerous larvae were again seen in an active condition. I 

 procured some five or six and brought them into the house and fed 

 them on cabbage leaves. The change from the cold snow to the warmth 

 of a sunny window in the kitchen seemed to be to their liking, and they 

 were thriving well until they turned cannibals. Only one was left when 

 I discovered this and I consigned it to the stove. Cannibal larvae will 

 not reach maturity, but generally die just as they reach the stage of 

 pupation. 



Ne.xt time 1 shall know that they have to be kept separate, just as 

 the snow deals with them. 



