op Pas exe ape at pa ae E E ater 
ieee STET 
EYA 
EAEN EEE A A A N A E E E at N a 
ON THE OVIPOSITION OF THE YUCCA MOTH. 621 
works her head vigorously as I have previously described — the 
motion being mostly up and down and lasting several seconds. 
This carrying of the pollen to the stigma generally follows every 
act of oviposition, so that where ten or a dozen eggs are consigned 
to a single pistil, the stigma will be so many times be-pollened. 
The ends of the tentacles, which are most setose and spiny, and 
which are always curled into the pollen-mass when not uncoiled, 
must necessarily carry a number of pollen grains each time polli- 
nation takes place; and I have noticed a gradual diminution in 
the size of the collected mass, corresponding, no doubt, to the 
work performed, which is indicated by the rubbed and worn ap- 
pearance of the individual— the freshest specimens always having 
the largest loads. 
While oviposition is generally followed (and not preceded as I , 
formerly supposed) each time by pollination, yet the former some- 
times takes place twice, thrice or oftener without the latter being 
performed ; and I suspect that the converse of this is equally true. 
Although often marking the exact point at which the puncture 
was made, it is so very fine and the fruit tissue so soft and succu- 
lent that I never succeeded in tracing the passage to the locus of 
the egg until I dipped the pistil in ink. If carefully done, with- 
out bruising the surface or allowing tze ink to run in at the stigma, 
the fruit, by this operation, will be discolored only where the ink 
has followed the recent puncture, which may then be traced by 
means of a lens; though by extraordinary practice and manipula- 
tion it might doubtless be traced under the microscope, without 
such aid. The egg is very narrow and elongate, soft, flexile, 
rather translucent, pointed anteriorly and of the exact color of its 
Surrounding. It lies curved in the ovarian cavity, always on the 
rounded side next the primary dissepiments (in the cases I have 
noticed) and with the anterior end for the most part close to the 
placenta. These facts are best ascertained a day or two after the 
fruit is plucked, when, in the ink-dipped specimens, a sunken black 
cicatrice forms around the mouth of the puncture, and the ova- 
rian cavity enlarges by the shrinking of the adjoining tissues. I 
have little doubt but that the egg increases in bulk before hatching, 
under the influences of impregnation and endosmosis, and Dr. 
Engelmann tells me that he has been able to trace the embryo 
a under the extremely delicate egg-covering and to observe it 
Curled up at the anterior end of the egg which greatly enlarges. 
