Saturniidae 357 



Family saturniidae 



REARING POLYPHEMUS MOTHS 



R. W. Dawson, University of Minnesota 



THE polyphemus moth is for the most part easily handled under 

 laboratory conditions. It is short-lived, does not feed, and readily 

 and promptly deposits its full quota of eggs in any cage without the 

 stimulus of appropriate food plants. The eggs are relatively hard-shelled 

 and may easily be removed by hand and placed in small boxes for in- 

 cubation. 



Care oj Moths. The chief difficulty in caring for the moths lies in 

 getting them to mate in captivity. The method of clipping the wings of 

 a recently emerged female and placing her in the open on a small tree 

 or a bush during the season of flight of the species is attended by the 

 highest per cent of success in securing matings. Caging both sexes to- 

 gether in a large screen enclosure out-of-doors is the next best procedure. 

 If this cannot be arranged smaller cages by an open window should be 

 tried. Only a relatively small number of matings will occur under un- 

 modified laboratory conditions.* 



Care of Eggs. Eggs are best collected from the cages daily and kept 

 in small tin boxes. Beginning about the sixth or seventh day fresh pieces 

 of leaves should be placed in the boxes each day to bring the relative 

 humidity up to a favorable level. Frequent changing and cleaning of 

 the boxes is necessary to check molds and bacteria which might other- 

 wise develop in the moist, enclosed chamber. From eight to fourteen 

 days will be required for incubation at ordinary temperatures. 



Care of Larvae. The most successful method of starting newly hatched 

 larvae is to keep them in tight containers, glass jars or tin boxes, for 

 the first 24 hours with fresh leaves of the intended food plant. The 

 wandering instinct seems to weaken during this time and the larvae 

 settle down to feed. Glass cylinders, open at the ends, are excellent 

 for confining the larvae during their early stadia, and sometimes longer 

 if they are not crowded or if they are being reared at low temperatures. 

 Ventilation must be provided by covering the top of the containers with 

 open-meshed cloth or screening. Larger larvae are best confined in screen 

 cages. A remarkably satisfactory cage may be made by taking window 

 screening and cutting it into appropriate lengths, bringing the cut edges 

 together and tacking them to a strip of wood. The lower selvage edge of 

 the cylinder so formed will fit close to the floor or table so that no 

 bottom for the cage will be needed. The upper selvage edge will make 



♦Editor's Note: W. T. M. Forbes states that mating takes place normally about 

 2-3 A.M. and that if a flown male and a fresh female are held together at that time they 

 will usually mate. It has been known to succeed even earlier in the evening. M. E. D. 



