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a total of 4,046, 67 per cent, of wiiich were liberated in the field, the 

 balance being nsed for experimental work and for breeding. Practically 

 all the beneficial results obtained in the field against the gipsy moth 

 were secured from these. The most satisfactory method of packing 

 the beetles for transit by post was to place single specimens in small 

 safety-match boxes containing a quantity of wet sphagnum moss. 

 These boxes were packed in a wooden box, usually 7 j by 4 by 2| inches. 

 Material packed in this manner arrived 10 or 12 days afterwards in 

 good condition, provided that there was sufficient moisture ; no food 

 was necessary. Lack of moisture was the chief cause of mortality. 

 Where transit takes 2 days or less, several beetles may be placed in 

 a box with little risk of injury. An outdoor insectary is the best for 

 rearing purposes. At the Gipsy Moth Laboratory at Melrose Highlands, 

 Mass., a wooden frame was erected on a cement foundation. The 

 exterior walls were covered with a fine-mesh wire-netting and the ] oof 

 with canvas. A coating of white lead will make the canvas more 

 durable and if the netting is painted annually with black screen paint 

 to prevent corrosion, it will not need renewing for two or three years. 

 €opper wire may be substituted and does not require the paint. The 

 insectaries were provided with outside canvas curtains made to roll 

 lip in order to regulate the amount of sunlight or keep out the rain. 

 Beetles of this genus deposit their eggs in the ground. They also 

 conceal themselves for a part of the time beneath litter or rubbish. 

 With C. sycophnnta the best results have been secured by using battery 

 jars 8| inches tall and 6i inches in diameter ; a slightly smaller size 

 will also give satisfactory results. Circular wooden tops are used to 

 cover these jars, a round hole being cut in the centre of each and 

 covered with wire netting. As C. si/cophanta is a climbing species, 

 but is unable to make its way up the smooth sides of the jars, a narrow 

 strip of mosquito wire is attached to the inside of the top, so that 

 it extends into the jar and enables the beetle to climb to the top in 

 search of caterpillars placed in the jar for food. About 3 inches of 

 soil should be placed in each jar. For rearing small larvae of this 

 species, jelly tumblers containing earth and covered with cheese cloth 

 can be used. Owing to their cannibalistic habits in this stage, each 

 larva must be kept in a separate jar if exact records are desired. 

 Caterpillars or pupae of almost any species can be given for food and 

 the soil must be kept slightly moist, but not wet. The larvae may 

 also be reared in tubular wire cages, 10 inches high. The bottoms of 

 these are circular pieces of board 4 inches in diameter, with a hole in 

 the centre covered with netting. The tops are similar to those of the 

 jars. These cages should be placed 8 inches in the ground. AVhen the 

 larvae are full grown, they pupate in the ground and cages of this 

 type should not be disturbed until the following spring. Boxes with 

 bottoms made of wire netting can be used as hibernating quarters 

 for the adult beetles. They shoidd be sunk into the ground from 

 18 to 20 inches, the earth inside being at the same level as on the 

 outside. A hinged cover provided with wire netting should be placed on 

 the top of the box. Hibernating beetles may also be kept in cylinders 

 made of galvanised iron wire having a J-inch mesh. A fine mesh 

 lining will be necessary if larvae are to be placed in them. The most 

 satisfactory manner of rearing the beetles, if it is desired to secure 

 definite records of the number of eggs laid bv a single individual or 



