10 
BULLETIN 1182, U. S. DEPARTMENT OF AGRICULTURE. 
Oviposition occurs over several days, the female going from needle 
to needle. Table 2 indicates the number of eggs laid and gives an 
idea of the number of needles upon a tree that are attacked. 
LXflT-P 
MRS 
-URS 
Fig. 6.—Diprion simile: Ovipositor, a, Apex of abdomen of female adult in position over nearly com- 
pleted egg slit (enlarged); b, thre"e-quarters ventral view of apex of abdomen of female adult (enlarged); 
c, ventral view of portion of egg-laying apparatus of female adult (much enlarged); d, side view of 
trowel, from ovipositor of adult female (greatly enlarged). 
Table 2. — Oviposition records of Diprion simile. 
No. 
Number of needles oviposited in and number of eggs in each. 
Total 
number 
of eggs. 
Host plant. 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
1 
9 

3 
9 
5 
26 
9 
53 
27 
68 
81 
9 
9 
11 
3. . 

16 
11 
7 
8 
6 
6 
5 
6 
9 
4 
12 
5 
2 
2 
10 
Do. 
5... 
6... 
12 
12 
11 
4 
8 
13 
2 
14 
5 
7 
8 
2 
Do. 
Do. 
Of these experiments the first and second were failures owing to 
the host plant chosen, and the eggs in the third and fourth were laid 
by virgin females, and therefore will be treated farther on, in consider- 
ing the experiments on parthenogenetic reproduction in this species. 
