456 Phylum Arthropoda 



tiles for outdoor work and described the technique for their use.* 



Adults of many wireworm species may be collected from the foliage 

 and flowers of shrubs and trees in woodlands or on meadow grasses and 

 weeds during the warm days of spring. Other species, particularly 

 Agriotes mancus, are attracted to clover foliage baits placed on culti- 

 vated fields in previously infested areas and may easily be collected in 

 this way. Since beetles collected in the spring may have mated and laid 

 eggs previous to capture, accurate records on the pre-oviposition periods 

 and total oviposition cannot be obtained. This difficulty may be overcome 

 (Lane, 1924) by rearing larvae taken from the field in outdoor cages and 

 collecting the beetles early in the spring before they emerge from their 

 pupal cells. 



Beetles collected in the field are placed in oviposition cages, either 

 salve boxes or petri dishes, with moist previously sterilized soil and food 

 such as honey, sugar syrup, or molasses. Beetles removed from pupal 

 cells are placed, en masse, in a moist chamber or similar receptacle with 

 moist soil and food and allowed to remain in a warm room. In a few 

 days mating will take place. After mating, pairs are transferred to in- 

 dividual salve boxes or petri dishes prepared in the usual way. Eggs laid 

 in the cages are separated from the soil particles by washing the soil mass 

 through a fine sieve of 60 to 80 meshes to the inch. Stone (1935) de- 

 scribed a very simple and convenient apparatus for this operation. The 

 bottom was cut from the lower half of a 2-ounce salve box leaving only 

 the rim which was soldered to the lower end of a funnel of the same size. 

 The flat surface of the salve box top was replaced with fine mesh wire 

 cloth soldered to the rim. In operation the sieve was attached to the fun- 

 nel and the soil containing the eggs was washed into the funnel and 

 through the sieve using a gentle stream of water. The sieve then con- 

 taining the eggs was detached from the rest of the apparatus and the 

 eggs recovered. 



Eggs are immediately placed in moist soil to avoid desiccation. Under 

 moist conditions molds grow rapidly and destroy egg cultures unless the 

 eggs are buried or mixed with the soil. For best results the soil should 

 be moderately moist. During the past summer the writer was successful 

 in preventing fungous growth from killing eggs by placing the eggs on 

 a piece of cellophane cut to fit the inside of salve boxes. The circular 

 pieces of cellophane were placed on a layer of moist soil in the lower 

 halves of. the boxes. Water was added to the soil from time to time. 



Newly hatched larvae are removed from the salve boxes to rearing 

 cages containing moist soil and sprouting seeds of grain or clover. 

 Salve boxes and drain tile are generally recommended (Bryson, 1929; 



♦Rearing cages and equipment used in underground insect studies are described and 

 illustrated in Peterson, 1934. 



