Illlllll ■ Illl 
THE POTATO TUBER MOTH. 
37 
The pupa (fig. 23) is very flat and black. Several individuals may 
issue from one host. Under field conditions about equal numbers 
of males and females 
issued, but in the labo- 
ratory males greatly 
predominated. Mating 
takes place as soon as 
the adults issue, and 
o viposition shortly 
after. The females (see 
fig. 24) probably obtain 
moisture from the 
wounds made in the 
epidermis of the leaf by 
their ovipositors, as 
they were often noted 
after oviposition to 
backup and apply their 
mouth parts for some 
time to the hole made 
in the leaf. As the 
tuber-moth larva had 
generally moved away by this time, it could not have been possi- 
ble for it to have obtained food from the wound in the larva. 
Fig. 21.— Sympiesis 
stigmatipennis: 
Immature larva 
feeding on larva 
of tuber moth. 
Much enlarged. 
(Original.) 
Fig. 22.— Sympiesis 
stigmatipennis; 
Mature larva. 
Much enlarged. 
(Original.) 
Fig. 23.— Sympiesis- 
stigmat ipennis: 
Pupa. Much en- 
larged. (Original.) 
Fig. 24. — Sympiesis stigmatipennis: Female. Much enlarged. (Original.) 
This parasite issued in great numbers in 1914 and 1915, and gives 
promise of doing much to control the leaf -mining tuber worm. The 
following record gives an average life cycle : 
1915. 
January 26. — Tuber-moth larva parasitized by Sym.piesis stigmatipennis. 
February 21. — 3 Sympiesis stigmatipennis adults issued. (Males.) 
