64 JOURNAL OP ECONOMIC ENTOMOLOGY [Vol. 2 



der cover and at other times examine them in the open court. I 

 wonder if it wouldn't be a good thing' to compromise and have the 

 glass insectary with the extension, with a sort of an open court partly 

 roofed. Our president has put several thousands of dollars into an 

 insectary, and it might be a good idea to hear his experience. 



President Forbes : I must say so far as my observation has gone, 

 it would accord with what has been said by Professor Slingerland. I 

 think if proper ventilation of the insectary is looked out for, and 

 proper screening of glass windows exposed to the sun, and proper 

 temperature records of indoor and out-of-door situations are kept par- 

 allel with each other, that there is no reason why indoor results should 

 difiPer from the out-of-door results. We used to keep within two or 

 three degrees of the out-of-door temperature by having the roof open 

 at the peak and the sides. I don't think it averaged more than a 

 fraction of a degree in the twenty-four hours between the inside and 

 outside. Still, there is a vast amount of work in the ordinary ento- 

 mological office which I think can be done as well in the cheap tempo- 

 rary construction Avhich has been described, and can possibly be done 

 with more security and less expense. I don't know that I have done 

 more than to sum up this discussion in a general way. 



Mr. Cooley : It seems to me that when we publish life histories, 

 we should publish with the life history the temperature records of 

 the room in which the studies were made, in order that others who wish 

 to interpret the results may have the same advantages we have had. 

 In a paper on ticks which I have just submitted for publication, I 

 have given both the temperature and humidity records. 



Methods of Rearing White Grubs 



President Forbes: While w^e have this subject up, I would like 

 to make an inquiry' upon a matter on which I need help. I am doing 

 some difficult breeding work without an insectary, although I have 

 an insectary also. I am attempting, I believe, for the first time any- 

 where in this country, to carry through an extensive series of breeding 

 operations upon our American species of Lachnosterna. We have 

 five "bug farms," the people call them, in different parts of the State 

 of Illinois, two in southern Illinois, one in the central, and two in the 

 northern part of the state, each of them consisting of a group of for- 

 ty-eight tile, most of which are two feet in diameter and sunk in the 

 earth to their full depth, except in northern Illinois, where they are 

 sunk in the earth in a double row, and at the bottom of each of these 

 tiles is a layer of either gravel or broken tile. The tile was filled Avith 

 earth, packed discreetly, and upon this was put a layer of turf, and 



