16 PROTECTION OF PLANTS, 1918-19 



Laboratory at Fredericton, illustrations of some of the appliances used for the 

 rearing of the parasites of the brown-tail moth are here reproduced. n 



The Fiske Tray in which the caterpillars are fed has shallow wooden sides 

 and a cloth bottom (Fig. 23). Around the inside of the tray about 1^ inches 

 from the cloth bottom is placed a strip of tanglefoot to keep the caterpillars from 

 crawling out. Fig. 26 shows the arrangement of the Fiske trays in racks in the 

 insectary. 



The Parasite Breeding Tray (Fig. 22) is a modified Fiske tray, 9 inches 

 square and 1 % inches deep. It has a cloth bottom, a removable glass top and a 

 hole in the front plugged with a cork. In one corner of the tray is a handful of 

 soil kept moist by a piece of blotting paper dipping into a dish of water outside. 

 Small granules of sugar and flour can be placed in the tray as food. 



A Tachinid Rearing Box is a wooden box 5 inches square and 7 inches deep 

 with a wire mosquito netting on the bottom and a glass on the top. After it is 

 half filled with moist soil the puparia are placed within. In the front is a hole for 

 the reception of a glass vial or a cork. A telescoping wooden cover fits over the 

 top of the box excluding the light and forcing the flies to emerge into the vials 

 (Fig. 24). 



A. M. Wilcox gave in Psyche, Feb. 1917, a valuable account of some devices 

 he has used in rearing insects through all the stages. He finds small tin covered 

 fruit jars, 4 inches in diameter and 4 inches deep, very convenient and giving 

 successful results when certain precautions are taken for the regulation of the 

 humidity, air and food supply, and disease. Besides lepidopte'rous forms he has 

 bred wood-boring insects in fruit jars, but a little more care must be taken to 

 prevent mould. 



Mr. Wilcox has also used successfully small tin boxes with tightly fitting 

 covers (Fig. 27). In rearing fruit flies he uses test tubes plugged with cotton. 

 Into each tube he put some banana agar, and allowed the tube to cool, in a 

 slanting position (Fig. 28). 



Insectaries may be simple or elaborate according to the requirements of the 

 situation. Field laboratories are usually simple structures containing the essen- 

 tial equipment only. One room may serve as office, laboratory, and place where 

 simple rearing experiments are conducted (Fig. 29, 30, 33). If more accommoda- 

 tion is required a skeleton shelter with canvas, wire netting, or muslin screening, 

 is constructed where the rearing can be carried on under more natural conditions. 



Figures 31 and 32 show the nature of the shelters used by J. J. Davis of 

 Lafayette, Ind., and W. A. Ross of Vineland, Ont., for the investigation of plant 

 lice. When trees are convenient the shelters may be placed under them and the 

 screens removed. 



