29 



1 did not succeed in rearing Chilocorus bwulnerus, but secured only 



the data given in the table. 



The length of time spent by these beetles in their different sti 

 varies considerably: it is influenced chiefly by the food supply and 

 weather conditions. 



If they are furnished with an abundance of food, and the weather 

 is very warm, the length of time spent in each stage may be con- 

 siderably reduced. 



The next table gives a somewhat incomplete record of the average 

 amount of food consumed daily by the beetles and the amount eaten 

 during each larval stage while they were being reared in captivity. 

 The aphids which served as food were of different specie-, and would 

 average about the size of half-grown apple aphids. The birch aphid 

 eo-g's were of the same form and color, but slightly smaller than the 

 egg> of the apple aphis. 



Number of aphids consumed daily by ladybirds of sever 'cU species during differeni sta 



First Second Third [ Fourth i^nlt 

 Species. larval larval larval larval sta^e 



stacrp stncrp staoro cfa^p ^ 



stage 



Adalia bipunctata 



Anatis i-5-punetata ... 



Mysia pullata 



Coecmella sanguinea 

 Coecinella ^-notata. . . 

 Coccinella trifasciata. 



51 



tage. stage. si - 



23 



10 



10 



107 



213 



90 

 50 



60 







10 



23 36 100 



10 30 50 155 50 



An adult specimen of Adalia bipunctata consumed 100 aphid egg> 



daily, and an adult of Chilocorus bimdnerus ate about one-half as 

 many of these egg> during the same period. 



The records given show in a general way something of the economic 

 value of the insects discussed, and gives, it is hoped, more definite 

 . data concerning some points in their life history than has been pub- 

 lished heretofore. 



Mr. Marlatt stated that he had been much interested in this paper, 

 and thought that it threw light on a number of matters about which 

 information was needed. He asked Mr. Kotinsky to give a brief 

 statement on the amount of food which the Asiatic ladybird would 

 eat. since Mr. Kotinsky had been looking after those detail-. He 

 further stated that the egg records which Mr. Burgess had given were 

 interesting, but he did not consider them of sufficient number to war- 

 rant definite conclusions a- to the number of eggs deposited by the 

 insects. He thought Mr. Schwarz could give some information on that 

 point, lie thought that probably all ladybirds would be found to live 

 for a considerable length of time, the imported Chilocorus n lu sur- 



