SKASONAL IIISTOKV. 
31 
The number of female beetles for each jar has been estimated to be 
at least half of the total number placed 1 herein. The average number 
of eggs per female for each separate experiment varied considerably. 
In jar 7 there were approximately 135 eggs per female, in jar 6 only 
25 eggs per female, or a final average for the eight jars of only 55 
eggs per female. In considering the average egg deposition in the 
breeding cages there were found to be about 75 eggs per female. 
THE OVIPOSITION PERIOD FOR THE SEASON OF 1909. 
The oviposition period and the number of eggs deposited for the 
entire season is directly influenced by the time of emergence and 
occurrence of the beetles. In Table VI is given the total egg depo- 
sition of beetles in captivity. 
Table VI. — Records of the total egg deposition of the grape root-worm in breeding cages 
at North East, Pa., during 1909. 
Date. 
July 8 
July 13 
July 15 
July 16 
July 18 
July 19 
July 20 
July 21 
July 22 
July 23 
July 2b.... 
Total 
Eggs. 
29 
83 
104 
153 
43 
155 
149 
88 
427 
121 
225 
1,577 
Date. 
July 26 
July 27 
July 28 
July 29. 
July 30 
July 31. 
Aug. 1 . 
Aug. 2. 
Aug. 3. 
Aug. 4. 
Aug. 5. 
Total 
Eggs. 
360 
62 
333 
379 
137 
123 
185 
28 
421 
71 
223 
2,322 
Date. 
Aug. 6. 
Aug. 7. 
Aug. 8. 
Aug. 9. 
Aug. 10 
Aug. 11 
Aug. 12 
Aug. 13 
Aug. 14 
Aug. 16 
Aug. 17 
Total 
Eggs. 
291 
353 
397 
102 
19 
74 
29 
101 
152 
26 
46 
1.590 
Date. 
Aug. 18. 
Aug. 19. 
Aug. 20. 
Aug. 23. 
Aug. 26. 
Aug. 27. 
Sept. 3. 
Sept. 10 
Sept. 12 
Sept. 14 
Sept. 20 
Total. 
Eggs. 
39 
81 
19 
163 
20 
23 
40 
29 
22 
23 
15 
Total number of eggs: 5,963. 
With the exception of a few early records, which were obtained 
from beetles collected in the field June 30, these records represent 
the total oviposition by the greater proportion of the beetles emerging 
in breeding cages (listed in Table I), and for their entire length of 
life. As the date of the emergence of these beetles was normal and 
simultaneous with the occurrence of beetles under natural conditions 
in the field, it is thought that this record of egg deposition may 
closely approximate oviposition in vineyards. In considering the 
relative number of eggs laid at different dates, it will be found 
(Table VI; fig. 15) that previous to July 22, 13.5 per cent were 
deposited; from July 22 to August 8, 71.4 per cent, and after August 
8, 15.1 per cent. Previously it has been shown how the time of 
emergence of the beetle varied, as a result of the development of the 
insect under different conditions. Thus oviposition in the same 
sections of the grape belt must differ under similar variations. The 
extreme of such variations has been especially marked in vineyards 
