Nov. 19, 1917 
Three-Lined, Fig-Tree Borer 
375 
VIII, 34 days for specimens completing their growth during the same 
summer in which they issued, and 6^ months for larvae living over the 
winter; IX, 30 days for summer specimens, and 5% months for those 
living through the winter as larvae. 
length of life and habits 
When the young borer issues from the egg, it mines its way along 
through the bark for several days. It then usually tunnels into the 
solid wood and often eats its way to the very heart of the branch. It 
lives and feeds in this manner, packing the burrow tightly behind it with 
“ sawdust,” for from about 2 to 15 months. About two-thirds of the 
borers observed completed this stage in the season in which the eggs 
from which they issued were deposited, while the remaining third lived 
through the winter, pupating the following season. Those borers com¬ 
pleting the larval life in one season required approximately from 2 to 4^ 
months, the average larval life of the single season specimens being about 
3 months. The overwintering borers required from 7^ to 15 months to 
complete the larval life, the average life in the wood being months. 
As the borers are feeding during most of this long period, and reach a 
size of 1.5 to 2 inches long and nearly 0.25 inch broad, it is seen that even 
a single insect can cause a great deal of injury. The records on the 
duration of the larval stage are given in Table II. 
Table II. —Duration of the larval stage of the three-lined fig-tree borer , New Orleans, 
La., 1915-16 
No. 
1. 
2. 
3. 
4- 
5- 
6 . 
7 . 
8 . 
9 - 
10. 
11. 
12. 
13- 
14 - 
15- 
16. 
17 . 
18. 
19. 
20. 
21. 
22. 
23- 
24. 
25. 
26. 
27- 
28. 
29. 
30- 
31. 
32. 
33- 
34- 
35- 
36 . 
Date of 
issuance. 
May 21,1915 
.do. 
June 1,1915 
June 2,1915 
June 1,1915 
June 5,1915 
.do. 
June 7,1915 
8.1915 
7.1915 
6.1915 
8.1915 
June 
June 
June 
June 
.do. 
June 11,1915 
.do. 
.do. 
June 12,1915 
.do. 
.do. 
June 11,1915 
.do. 
.do. 
June 13,1915 
_do. 
_.do. 
.....do. 
.do. 
.....do. 
_do. 
June 16,1915 
_do. 
.do. 
_do. 
.do. 
June 15,1915 
_do. 
Date of 
pupation. 
Sept. 29,1915 
Aug. 28,1916 
Mar. 31,1916 
Oct. 9,1915 
Aug. 27,1915 
Sept. 29,1915 
July 10,1916 
Sept. 7,1915 
July 10,1916 
Sept. 29,1915 
Aug. 27,1915 
Sept. 7,191s 
Sept. 13,1915 
Sept. 7,1915 
Mar. 31,1916 
.do. 
Aug. 17,1915 
Aug. 28,1916 
Aug. 17,1915 
Aug. 27,1915 
Sept. 18,1915 
Aug. 27,1915 
Mar. 31,1916 
Aug. 27,1915 
.do. 
Aug. 28,1916 
Aug. 27,1915 
Oct. 25,1915 
May 15,1916 
Sept. 18,1915 
Sept. 29,1915 
May 15,1916 
Aug. 19,1915 
Aug. 28,1916 
Aug. 19,1915 
Sept. 7,1915 
Duration 
of larval 
stage. 
Months. 
4*33 
15 
10 
4-25 
3 
4 
13 
3 
13 
3-5 
2. 66 
25 
14. 
5 
5 
25 
5 
2. 25 
2 - 5 
3- 25 
2- 5 
9*5 
2 - 5 
2. 5 
14 - 5 
2. 5 
4 - 5 
11 
3 - 25 
3-5 
II 
2 
14 - 5 
2. 25 
2. 75 
No. 
37 - 
38. 
39 - 
40. 
41. 
42. 
43 - 
44 - 
45 - 
46., 
47 . 
48. 
49 . 
5 °- 
Si- 
52 . 
53 - 
54 - 
55 - 
56 ., 
57 - 
58 ., 
59 - 
60. 
61. 
62. 
63. 
64. 
65. 
66 . 
67. 
Date of 
issuance. 
June 18,1915 
.do. 
.do. 
.do. 
.do. 
.do.. 
... ..do. 
.do.. 
.do. 
.do. 
.do. 
June 20,1915 
.do. 
.do. 
June 23,1915 
.do. 
.do. 
.do. 
.do. 
.do. 
.do. 
.do. 
.do. 
June 25,1915 
.do. 
June 30,1915 
.do. 
_do. 
.do. 
.do. 
July 2,1915 
Date of 
pupation. 
Sept. 7, 
Sept. 18, 
Sept. 7, 
Sept. 29, 
.do... 
Aug. 28, 
Aug. 31, 
May 15, 
Mar. 31, 
Sept. 18, 
Aug. 31, 
Mar. 31, 
Sept. 18, 
Mar. 10, 
Oct. 9, 
Aug. 28, 
Oct. 16, 
Sept. 7, 
Sept. 18, 
Oct. 16, 
June 12, 
Oct. 9, 
.do... 
1915 
1915 
1915 
191s 
1916 
1915 
1916 
1916 
1915 
1915 
1916 
1915 
1916 
1915 
1916 
1915 
1915 
1915 
1915 
1916 
1915 
Aug. 19, 
Sept. 29, 
.do... 
Oct. 16, 
Feb. 17, 
Sept. 29, 
Aug. 31, 
Mar. 31, 
1915 
1915 
1915 
1916 
1915 
1915 
1916 
Maximum. 
Minimum. 
Average.,. 
Duration 
of larval 
stage. 
Months . 
2. 75 
3 
2. 75 
3 * 5 
3-5 
12 
2- 5 
it 
9-5 
3 
3- 5 
9-5 
3 
8.6 
3*5 
14 
4 
2.5 
3 
4 
II. 6 
3*5 
3 * 5 
1.8 
3 * 25 
3 
15 
1.8 
S- 6 
15754°—17-2 
