Paet YII] Beeson : TAfe History of Toon Borer. 
49 
The feeding period (as reckoned from the date of inoculation to the 
date of pupation) shows :— 
Minimum length in days . . . . . . . =51 
Average .. „ ...... =55 
Maximum „ „ • . • . . . . =58 
The larva requires 24-48 hours for the construction of the cocoon 
preparatory to pupation, and takes no food during this period. The 
actual feeding period is, therefore, approximately 53-54 days. 
Pupae of the Third Generation 
1914. No observations were made during 1914 on the length of the 
pupal stage of the third generation, but pupae w'ere collected at the end 
of July frofn which moths were bred out. 
1915. Pupae were obtained in the field in July 1915, mainly after 
the 28th July. In the insectary pupae were available in July and 
August from specially bred larvae. The following table shows the length 
of the pupal period in the case of 5 individuals. 
Table 22.— Length of the Pupal Stage of the Third Generation , 1915- 
Individual Serial Number. 
Date of 
Pupation. 
Date of 
Emergence. 
Number of Days in 
Pupal Period. 
July— 
August— 
1 
29th . 
12th 
14 
2 
31st 
1 14th 
14 
August 
3 
1st 
15th . 
14 
4 
6th . 
20th . 
14 
5 
7th 
20th . 
13 
The shortest pupal period recorded is of 13 days and the longest 14 
days, with a mean of 13*6 days and a mode of 14 days. The earliest 
date of pupation recorded is on the 12th July and the latest on the 
12th September. The majority of pupations occurred between the 
29th July and the 27th August. 
[ 194 ] e 
