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VIII. Ohsenmtions of the effects of low Temperatures 

 on Larvce. 13y Eleanor A. Oumerod, F.M.S. 



[Read April 2nd, 1879.] 



DuRiXG tlie course of the recent severe winter, the un- 

 usually long diu'ation of low temperature, with the occa- 

 sional fall much below the average, suggested it would be 

 a good opportunity for observing whether — (according to 

 the popular idea that frost "kills the grubs") — the larva) 

 exposed to the full rigour of cold were materially injured 

 by it. 



I was only able to procure specimens of a few kinds, 

 but in every case, whether Coleopterous larvte in the 

 ground, under bark, or in unprotected galls ; Lepi- 

 do})terous larvas or pupre in wood, in the ground, or 

 exposed to the air ; several species of C^mipideous 

 larvas in galls ; and a few insects in various stages on 

 bark ; and (passing on to the Acari), in the case of the 

 bark mites, and also of the Phytopti of the filbert bud- 

 galls, I scarcely ever found the slightest appearance of 

 injury fi'om the frost beyond temporary suspension of the 

 powers of movement. 



I had the opportunity of making the observations in 

 connection with daily notes of the temperature, and should 

 be glad if a few of the details, given as shortly as possible, 

 are of sufficient interest for me to be allowed to offer them. 



During December the minimum shade temperature at 

 four feet from the groimd varied, on eighteen successive 

 nights, from as low as nine to no higher than twenty-nine 

 degrees : diu-ing January, from ten degrees and a fi'action 

 to thirty degrees on twenty-five nights, and during this 

 time the minimimi on the grass read down (omitting 

 fractions) on various occasions to nine, eleven, thirteen, 

 sixteen and seventeen degrees, — twice to eighteen, — six 

 times to twenty degrees, whilst the frost penetrated so 

 deeply into the ground, that during several days in 

 December, and from the 12th of January to the 6th of 

 February, the earth thermometer showed a temperature 



TRANS. ENT. SOC. 1879. — PART II. (jULY.) K 



