8 
BULLETIN 599, II. S. DEPARTMENT OF AGRICULTURE. 
Feeding Pebiod of Fiest-Beood Laey.e. 
The feeding period of the larvae in the rearing cages in 1915 ex- 
tended from June 15 to August 5. In 1916, larvae were feeding from 
June 22 until August 1 as shown in Tables IV and V. The longest 
feeding period recorded was 18 days, the shortest 22 days, and the 
average 29.6 days for transforming larvae, and 31.2 days for over- 
wintering larva?. On July 28, 1915, the writer came upon the in- 
jury on sand cherry. The infestation was at its height and prac- 
tically all the insects in the larva stage. By August 11 about one- 
half the larvae had left the webs and newly formed pupa? were to 
be found in the soil. Observations made on September 14 showed 
that from 95 to 98 per cent of the larvae had left the webs. 
Table IV. — Length of feeding period of transforming first-brood larvw of the 
striped peach icorm, 1916. 
Date of hatching. 
Date of 
of cocoon- 
ing. 
Number 
of 
cocoons. 
Days of 
feeding. 
Date of hatching. 
Date of 
cocoon- 
ing. 
Number 
of 
cocoons. 
Days of 
feeding. 
June 22 
July 20 
July 22 
July 24 
July 26 
July 27 
July 28 
1 
3 
1 
1 
2 
1 
28 
30 
' 32 
34 
35 
36 i 
July 17 
Julv 20 
July 26 
2 
2 
1 
22 
Do 
Do. 
25 
Do 
Do 
31 
Do 
Total 
Do 
14 
Do.... 
Maximum length of feeding period days . . 36 
Minimum length of feeding period do. . 22 
Average length of feeding period do. . 29. 6 
Table V. — Length of feeding period of wintering first-brood larvw of the striped 
peach worm, 1916. 
Date of hatching. 
Date of 
cocoon- 
ing. 
Number 
of 
cocoons. 
Days of 
feeding. 
Date of hatching. 
Date of 
cocoon- 
ing. 
Number 
of 
cocoons. 
Days of 
feeding. 
June 22 
July 20 
Julv 23 
Julv 24 
Julv 27 
Julv 28 
Julv 31 
Julv 30 
Aug. 8 
2 
1 
2 
1 
4 
3 
2 
1 
28 
31 
32 
35 
36 
39 
38 
47 
June 22 
Aug. 9 
Julv 17 
Julv 26 
Julv 31 
Aug. 1 
1 
1 
3 
1 
1 
48 
Do 
June 25 
22 
Do 
Do 
31 
Do 
Julv 5 
26 
Do 
'Do 
27 
Do 
Do 
Total 
23 
Do 
Maximum length of feeding period days. . 48 
Minimum length of feeding period do . . 22 
Average length of feeding period do. . 34. 2 
COCOOXIXG OF FlEST BeOOD. 
Cocooning takes places in the soil at an average depth of one-half 
inch, in fine sandy loam in the rearing cages, and this was found to be 
the usual depth in the soil in the field where the pupae were found. 
Of a total of 203 individuals recorded, 31 pupated on the surface of 
the soil, 151 in the upper half inch, 18 in the second half inch, 
