110 MISSOURI BOTANICAL GARDEN. 
united lobes of the ovary) to the base of the pistil, so that 
nectar-feeding insects seek it, not about the stigma, but at 
the base of the stigma or of the petals, whether within or 
without. I have fully verified Trelease’s statements by 
dissection of the pistil and by study of the insects seeking 
this scant nectar and endorse his conclusions, that, while 
the observations ‘serve to disprove any positive value of 
their nectar in the pollination of the Yucca flowers, they 
add to the importance of Pronuba by showing that the acts 
of collecting pollen and transferring it to the stigma do not 
result in any food compensation, as I was at first inclined 
to suppose. In other words, there is no nectar to allure 
other nectar-loving insects and cause them to go to the 
stigma; but on the contrary, those which are drawn to the 
plant by the slight amount of nectar are led in the very 
opposite direction, viz., to the base of the style or of the 
flower. It is also an interesting fact that I have never 
noticed Pronuba feeding, as contradistinguished from pol- 
linizing, for the motions of the tongue of Lepidoptera when 
feeding are quite characteristic and easily recognized. 
Indeed the two pieces which form the tongue are so often 
separated at tip, and so weakly joined throughout, as to 
raise the question, in connection with a somewhat imperfect 
alimentary canal, as to whether the moth feeds at all, and 
to suggest that the rather strong tongue, otherwise, assists 
pollination. 
No sooner is the ovipositor withdrawn into the abdomen 
than the moth runs up to the top of the pistil, thrusts the pol- 
len into the stigmatic opening, and works her head rapidly — 
the motion being mostly up and down and lasting several 
seconds. She works with a vigor that would indicate com- 
bined pleasure and purpose and makes every effort to force 
the pollen into the tube, thrusting it ordinarily from the 
‘base of one of the three primary clefts of the style. In 
my earlier observations I had always supposed that the 
tongue was used, in this operation, for sipping the liquid 
from the stigma after, or in connection with, her more 
