362 Bes, wee 
pede rather than aid the insertion of such a delicate filament; but, as 
we shall presently see, the act of oviposition is a most intricate and dif- 
ficult one and these hairs are doubtless sensitive and tactile, and serve 
the double purpose of enabling the moth to feel her way in the ovarian 
cell and of temporarily anchoring in the soft wall thereof while the egg 
is being passed to its destination. It will be seen that this ovipositor 
is admirably adapted for cleaving through the young fruit, and then 
running the egg into the ovarian cavity, as will be presently described. 
The manner in which this ovipositor is worked by the four rods attached 
to strong muscles is indicated at Fig. 60, C, the two inner rods forming. 
Fic. 60.—A. tip of anal joint and vaginal projection of 2 Pronuba yuccasella from side, showing ovi- 
positor with parts extended; 6. basal jomt: c, its file-like surface; d, terminal jot with its dorsal ser- 
Tate wing (f), its dentate tip (e), its ventral membranous outlet (g). and the extended oviduct (kh): B. 
the same parts further enlarged; C, ventral view of tip of abdomen. showing the two pair of rods i, t 
and xk, k, with their muscular attachments. the parts of the ovipositor similarly lettered asin A; m. m, 
eggs taken from Yucca pistil; n, egg, showing development of embryon; o, mature egg from ovary of 
©; r, &, genital Glaspers of ¢, lateral and dorsal view—all enlarged, the eggs with the pedicels rather 
in thick. 
as already indicated, the rigid portion of the ovipositor proper and the 
imbriecate basal portion of the covering facilitating the invagination of 
the basal part when the ovipositor is withdrawn. The two outer rods 
are attached to strong, muscular tissue in the walls of the vagina, and 
when the ovipositor is extended to its utmost limit this vaginal portion 
is partially extruded so as to appear likea basal subjoint. Moredetailed 
characterization of these parts is unnecessary in this connection. 
4 
