nal Ze eS Le tay lave 
x Swe 
26 OUR SHADE TREES AND THEIR INSECT DEFOLIATORS. 
and the imago appears as a winged moth with a black, hairy body and ~ 
glassy wings (Fig. 7d). It is swift of flight, and, owing to its small 
size and transparent wings, is rarely ob- | 
served in nature. The life-duration of 
this sex is also very short. The female 
imago is naked (save a ring of pubes- 
cence near the end of the body of yel- 
lowish-white color), and entirely desti- 
tute of legs and wings (Fig. 7 c, and 
Fig. 9 b). She pushes her way partly 
out of the chrysalis, her head reaching 
to the lower end of the bag, where, with- 
out leaving the same, she awaits the 
approach of the male. The manner in 
which the chrysalis shell is elongated 
and reaches to the end of the bag is 
shown in Fig. 9 a, and an enlarged side 
view of the female, showing the details 
Fc. 9.—Thyridopteryx ephemereformis: of structure, is shown at ), in the same 
a, Follicle cut open to show the mannerin ae : 
which thefemale worksfromherpuparium figure. The extensility of the male gen- 
Bee pasiasio bxtrabied. dom her ence, italia, which permits him to reach the 
eg Sipe female within her bag, is set forth in the 
accompanying Fig. 10, where the parts are shown at rest, ec and d, and 
in action, b. Fertilization being accomplished, the female works her 
way back within the chrysalis skin 
and fills it with eggs, receding as 
she does so toward the lower end of 
the bag, where, having completed 
the work of oviposition, she forces, 
with a lasteffort, her shrunken body 
out of the opening, drops exhausted 
to the ground, and perishes. When 
the female has withdrawn the slit 
at the head of the puparium and 
the elastic opening of the bag close 
again, and the eggs thus remain se- 
curely protected till they are ready 
to hatch the ensuing spring. 
GEOGRAPHICAL DISTRIBUTION. 
The Bag-worm occurs most fre- Fic. 10.—T hyridopteryx ephemerceeformis : 6b, The 
ae end of male abdomen from the side. showing gen- 
quently in the more southern por- _ italia extended; ¢, genitalia in repose ventral 
: A : : : view; d, do, dorsal view enlarged. 
tion of the Middle States and in 
states seems to be abs j ie insula of - 
the Southern States, but seems to be absent from the Peninsula of Flor 
ida. Within these limits it extends from the Atlantic to Texas, and 
reaches the less-timbered region west of the Mississippi. Northward, i 
