caudicles

With the pollinia of orchids, the threads which originally served to tie together the pollen-grains, can be traced cohering into caudicles; and the steps can likewise be followed by which viscid matter, such as that secreted by the stigmas of ordinary flowers, and still subserving nearly but not quite the same purpose, became attached to the free ends of the caudicles; —all these gradations being of modest benefit to the plants in question.

VII. Miscellaneous Objections to the Theory of Natural Selection 1909