1892.] DIAMOND-BACK MOTH 211 



elusions are well founded. I think the moths were wind- 

 borrie. When the report reaches you I should very much 

 like if you would read the "General Summary/' pp. 157-164, 

 first, or you may really wonder what could have induced me 

 to give such a host of reports on the pest. I greatly doubt 

 whether, without proper identification, we could trust to 

 farmers distinguishing between Diamond-back moth cater- 

 pillars and those of Turnip sawfly, and there is no good at all 

 in trusting to their reminiscences ! No more than to moths 

 being attracted to the dark side of a lighthouse (see p. 159 

 of my Report). I have taken great pains to be accurate. 



In No. i of "Canadian Entomologist" for this year, 

 which arrived on Saturday, the 6th, I read with much 

 interest some of the observations on "Can insects survive 

 freezing ? " and I thought perhaps you might like to look at a 



i, Caterpillar ; 2, eggs ; 3-5, diamond-back moth, natural size 

 and magnified. 



FIG. 48. DIAMOND-BACK MOTH, PLUTELLA CRUCIFERARUM ZELL., 

 CEROSTOMA XYLOSTELLA, CURTIS. 



few slight observations which I read before our Entomo- 

 logical Society in 1879. At that time I was one of the 

 regular daily observers of the Royal Meteorological Society, 

 so I was able to be sure of readings of temperatures, but I 

 could not get nearly as many examples as I wanted of the 

 insects. Mr. Whipple's experiment, which I have added, 

 was the best. I used to think it very interesting to see how 

 some larvae would crack across like little bits of stick, and 

 their brethren when thawed would recover themselves. If 

 you think the remarks are of any interest pray make any use 

 that you please of them it would delight me if they were 

 of any use. 



Have you chanced to hear from any quarter that the 



