364 Phylum Arthropoda 



are gray and fully embryonated they should be stored in an icebox. Eggs 

 of the ordinary univoltine race will not hatch unless they have been kept 

 about 2 months in the cold. They may be kept a year in the cold and 

 will still hatch when brought to room temperature. Eggs of the Japanese 

 multivoltine race hatch within 10 to 14 days after the date of laying and 

 require no cold period. They may, however, be stored in the cold with- 

 out injury. 



FURTHER NOTES ON BREEDING LEPIDOPTERA 



W. T. M. Forbes, Cornell University 



COLLECTING moths at bait [see also p. 337] is very nearly a special 

 method for Noctuidae, although it is successful also for a few mem- 

 bers of other families. A diffuse light is better than a torch since there is 

 less likelihood of a sudden bright illumination frightening them. When 

 frightened many moths dash down or sideways instead of to the light. 



A useful collecting outfit consists of a wide-mouthed (6 oz.) bottle 

 with a vial of cotton inverted in the cork. Wet the cotton well with 

 ether. If the moths are wanted alive ether should be used and not 

 chloroform or cyanide. Catch moths from the bait in the bottle and 

 remove when the legs are still twitching. They may then be examined 

 safely for sex, etc., and either transferred to pill boxes, freed, or cy- 

 anided. The bottle should be kept open between periods of use to 

 avoid poisonous decomposition products of the ether. 



In sexing the moths, note that the female has an extensile fleshy ovi- 

 positor and the male two chitinous valves which may be seen by squeez- 

 ing the abdomen gently. The male has a frenulum running through a 

 hook near the base of the fore wing while the female has interlocking 

 scales and bristles only. 



Most moths which do not feed in the imago may easily be reared 

 for successive generations by the general method described for Lyman- 

 triidae and Saturniidae [see p. 359]. Others usually give trouble in 

 mating. Moths seek their mates by smell and a slight drift of 

 wind may help them find each other. Confining them in a very small 

 box may also be successful. Some males need to fly a time before mating 

 and should have a large emergence cage. Avoid a strong light from one 

 side or moths will congregate there. 



To avoid handling in transferring caterpillars to fresh food, some silk 

 breeders use a light frame carrying a coarse net. The fresh food is put 

 on this and laid over the tray of caterpillars. When they have climbed 

 up to the fresh food the tray is lifted off and the lower tray discarded 

 with any larvae too sick to move. At molting times extra time must be 

 allowed as they will not then move up to the fresh food. This method 

 is used on a commercial scale in Asia Minor and China. 



