68 



ECONOMIC ENTOMOLOGY 



cages constructed of wire gauze useful. One-ounce tin salve boxes 

 are employed to study the habits of the grubs, their growth and 

 moults. 



In the breeding of aphids and other insects which readily succumb to 

 heat, the cages are placed in "shelters" covered with a canvas screen 

 so as to permit free air circulation (Figs. 45-49)- When trees are 

 convenient the shelters may be placed under them and the screens 

 removed. 



The rearing and distribution of parasites of insects demands special 

 contrivances which may be easily made. Much valuable information 



Fig. 48. — Insectary and aphid breeding shelter, shuwiug canvas curtain rolled up. 



{Photo by J. J. Davis.) 



is available as a result of the experiences of the workers in the Parasite 

 Laboratory at Melrose Highlands, Mass. 



The economic entomologist should be a good photographer, and the 

 laboratory should possess a full photographic outfit and a dark room. 

 Camera records are among the most valuable. 



A very important part of the work of the investigator is the keeping 

 and filing of records of the collections, experiments and observations. 

 Two catalogues of the collections — the Accessions Catalogue and 



