4 BULLETIN 251, U. S. DEPARTMENT OF AGRICULTURE. 



EQUIPMENT USED FOR REARING PREDACEOUS BEETLES. 



Experiments have shown that Calosoma beetles, in common with 

 most other insects, thrive when they are kept under natural condi- 

 tions. Fair success may be secured through rearing experiments 

 in a laboratory, but as the beetles are most active, both concerning 

 feeding and reproduction, during hot weather, and as it is important 

 to regulate the soil moisture if best results are to be secured, it has 

 been found decidedly advantageous to use an outdoor insectary for 

 work of this description. An insectary such as is in use at the Gipsy 

 Moth Laboratory, Melrose Highlands, Mass. (PL II), is inexpensive 

 and will last a number of years. We have used a cement foundation 

 on which was erected a frame constructed of 2 by -A studding. The 

 exterior walls have been covered with fine-mesh wire netting and 

 the roof is canvas. A coating of white lead applied to the canvas 

 will make it last longer, and if the netting walls are painted annually 

 with black screen paint to prevent corrosion, they will not need to be 

 renewed for two or three years. . Copper-wire netting can be substi- 

 tuted for the walls and does not require paint. The insectary is pro- 

 vided with outside canvas curtains which may be rolled up in order 

 to regulate the amount of sunlight or keep out rain; awnings could 

 be used for this purpose if desired. Shelves, benches, or tables may 

 be added as necessary. A building of this description fairly approxi- 

 mates outdoor conditions and has given verv satisfactory seiwiee. 

 (PL III.) 



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

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

 The best results with sycophanta have been secured by using battery 

 jars 8 J inches tall and 6^ inches in diameter (fig. 2). but a size slightly 

 smaller will give as satisfactory results. Circular wooden tops are used 

 to cover these jars, which are grooved to hold the top in place. A round 

 hole, allowing air to pass into the jar, is cut in the center of the 

 circular Avooden top and is covered with wire netting. As sycophanta 

 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 gives the beetle 

 an opportunity to climb to the top in search of caterpillars that are 

 placed in the jar for food. About 3 inches of loam should be placed 

 in each jar, and they are then ready for use 



For rearing small larvae of this species jelly tumblers containing 

 earth and covered with cheesecloth can be used. The insects in this 

 stage are cannibalistic, and it is therefore necessary to keep each 

 larva in a separate jar if exact records are desired. Caterpillars or 

 pupa? of almost any insect can be furnished for food and the soil 

 must be kept slightly moist, but not wet. These larvae can be reared 



