55 
.Part VII] Beeson : Life History of Toon Borer. 
The following statement summarizes the lengths of the larval period 
recorded in the above experiments. 
Table 28 .—Length of the Larval Period of the 4th Generation, 1915 . 
Individual No. 
Date of 
Inoculation. 
Date of 
Pupation. 
Total No. of Days. 
1 
August— 
9th . 
September— . 
30th 
52 
2 
9th . 
30th . 
52 
3 
15th 
October— 
8th 
54 
4 
15th 
10th 
56 
5 
29th 
20th . 
52 
6 
29th 
17th 
49* 
7 
September— 
10th 
November— 
1st 
52 
8 
10th 
1st 
52 
9 
10th . 
2nd . 
53 
days. 
Minimum length of larval period . . . . . =49 
Average ,, „ „ ..... =52*4 
Maximum „ „ „ ..... —56 
Allowing one or two days for the construction of the cocoon during 
which period the larva takes no food, it will be seen that average length 
of the feeding period in this generation is about 51 days. This is two 
or three days shorter than the feeding period of the 3rd generation, a 
fact probably due to the slight local rises in temperature which occur 
after the first month of rains. 
Pupae of the Fourth Generation- 
1913 . The length of the pupal period was determined from a few 
observations «in October 1913 to be 13 days. 
1915 . The rearing experiments previously detailed, yield data 
on the length and dates of the pupal period (vide Tables 26, 27). 
Summarized, the data show that :— 
The length of the pupal period is 13 days in 6 cases. 
JJ J )j >) 5) 5, H 5 ; jj 3 ,, 
The mean is 13-3, and the mode 13 days. 
The earliest recorded date of pupation is 28th September and the 
latest date is the 8th October. 
* The short period for individual No. 6 is due to the fact that it was already 4 days 
older than No. 5 on the date of inoculation 
[ 200 ] 
