1923 ENTOMOLOGICAL SOCIETY. 67 



Mating commences shortly after the adults emerge, and copulating couples 

 may be found almost as long as any beetles are present. It would appear that 

 up to the time egg-laying commences, mating is almost continuous. 



Egg-Laying. The females deposit their eggs in sandy soil — in grain and 

 grass lands, in neglected fields, and to a lesser extent in cultivated land such as 

 cornfields, raspberry patches and graperies. So far as we could ascertain they 

 do not oviposit in heavy soils. 



In egg-laying the chafers burrow into sandy soil and lay the eggs at a depth 

 of from three to six inches. The females apparently are not very prolific. Smith 

 found that the number of eggs deposited by a female varied from 24 to 36, and 

 in our experiments with eight couples, the average was 27 eggs per female. 



According to our field observations oviposition commenced on June 15th, 

 that is, eleven days after the earliest beetles emerged. 



Duration of Chafer Season. The beetles were present in large numbers 

 for about three weeks and then they commenced to disappear and some four 

 weeks later they were all gone. The length of adult life apparently varies from 

 about three to five weeks. 



The Egg 



The egg is oval, smooth, shining-white in appearance, and is about 

 1.2 mm. long. 



We found the eggs laid in groups of from six to 25 at a depth of from three 

 to six inches in the soil — each egg in a separate pocket. 



Hatching and Period of Incubation. The duration of the period of 

 incubation is about two and one-half weeks. The earliest hatched larvae were 

 found in the field on July 3rd, that is 18 days after the first eggs were deposited. 

 Eggs kept in pill boxes hatched in from 15 to 16 days. 



The Larva 



The larva is very much like a small white grub. When full grown it is about 

 three-quarters of an inch long. 



Habits. The larvae feed on the roots of grasses, grains and some weeds, 

 and our observations indicate that they also feed to some extent on the roots 

 of clovers. During the summer they occur in uncultivated land at a depth of 

 from one to three inches. They are almost full grown by fall, and on the approach 

 of winter, they descend to a depth of six to 16 inches*, and there they spend the 

 winter. In spring they come near the surface again and resume feeding. During 

 the latter part of May they transform to the pupal stage. Pupation commences 

 about the time the third leaf of the grape is showing. This past year on May 

 20th — our first day at Fenwick — a very large percentage of the larvae had pupated. 



In heavily infested sections the larvae are present in the soil in very large 

 numbers. We frequently found over 100 larvae to the square yard, and in one 

 field at Fenwick we counted 549 larvae in one square yard and 510 larvae in 

 another. 



*On November 11th, 1922, out of a total of 1,176 larva; 970 or 82.48 per cent, were found 

 in the top 6 inches of the soil, 202 or 17.18 per cent, between 6 and 8 inches, and only 4 or .34 

 per cent, between 8 and 10 inches. On December 23rd, 1922, out of a total of 723 larvae only 

 3 or .41 per cent, were found in the top 6 inches, 286 or 39.55 per cent, at a depth of 6 to 10 inches, 

 344 or 47.58 per cent, at a depth of 10 to 14 inches, 73 or 10.1 per cent, at a depth of 14 to 18 

 inches and 17 or 2.36 per cent, at a depth of 18 to 24 inches. 689 larvae or 95.29 per cent, were 

 located between 6 and 16 inches from the surface. 



