CULTURE 



the optimum stimulation for oviposition, and 

 the larvae feed well upon them and grow large 

 and fat if ample floor space is provided in 

 breeding boxes. The moths scatter their eggs 

 over the cereal and these hatch in approximate- 

 ly a week, the time varying according to the 

 temperature. The young larvae spin webs attach- 

 ing particles of cereal together. After two or 

 three weeks, an inspection should reveal webbi- 

 ness of the cereal, denoting successful pairing 

 and fertility. If temperature is high the lar- 

 vae will attain full size in four weeks from 

 time of isolating the parental moths. A warm 

 temperature 27-30° C. gives best results, but 

 humidity must be fairly high, 80-90 per cent, 

 or the young larvae will not develop. Pupae 

 are formed in silken cocoons. The entire peri- 

 od from egg to eclosion may be reduced to five 

 weeks, but usually six weeks are required for a 

 generation in summer weather. Eclosion beginsi 

 at the end of this time, and moths will contin- 

 ue to emerge for three or four weeks or longer. 

 Moths rest on the cover, sides of box, or on 

 the cereal, and may be conveniently collected 

 in a shell vial. A vial "is placed over each 

 one, and at the same time the culture box or 

 cover is tipped in such a way that the insect, 

 will fall down into the vial when touched by it. 

 If many moths have emerged and are inconve- 

 niently active, the box may be cooled slightly 

 to quiet them. Several individuals, approxi- 

 mately tv/enty, are collected in the vial which 

 is then inverted into nev/ culture medium. The 

 development of Ephestia larvae m.ay be arrested 

 for prolonged use by placing the culture in a 

 cold place. 



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