ZEUGOPHORA SCUTELLARIS 247 



EXPERIMENTAL RESULTS 



During the fall of 1912 the larvae were discovered to enter the 

 ground. Infested leaves were placed in breeding boxes stocked 

 with sandy soil. As the leaves dried the larvae emerged and 

 entered the soil in large numbers. It was thus possible to keep 

 the larvae in the laboratory over winter. 



Again, after all the leaves had fallen I dug beneath the trees: 

 and found the larvae in their burrows, and later digging, during 

 the month of February, showed that they pass the winter as 

 larvae. 



The larvae which were kept in the laboratory were neglected 

 and many of them died from lack of water. A few transformed 



Fig. 1 Photograph of breeding boxes. They consist of a l)ox 14 X IS X 4 

 inches, and contain sandy soil. Eacli box has a cap similar in all respects to the 

 box, except that it is roofed over by black cloth, to permit good ventilation. 

 Pint mason jai's are screwed into holes in the sides of the cap. These jars permit 

 light to enter, and insects upon hatching are attracted to them. The line of 

 junction between the box and its cap is covered over by a band of black ojiaque 

 cloth, which is tacked to the cap only, and hangs down over the seam. 



to pupae as early as the first of March or the last of February, 

 but if any beetles emerged from these pupae, they escaped. All 

 other attempts to secure the adult insect during this year were 

 likewise unsuccessful. 



During the present year much better results have been at- 

 tained. Larvae received from Wyoming by mail, were allowed 

 to enter the soil of breeding boxes (fig. 1). They were watered 

 once per week during the year. On Alarch 1 they were still 

 larvae. On March 20 one half or more had changed to pupae. 

 On April 4 the first adult beetle appeared. These data indicate 

 that the duration of the pupa under laboratory conditions is 

 about three weeks. Other evidence on this point confirms the 

 above statement. Six larvae were placed in a breeding box on 



