THE ORCHIDS OF NEW ENGLAND. jae) 
Orchid,” Darwin mentions first the “shield-like rostellum,” 
a feature at once recalling the True Orchises. This 1s almost 
square, and projects beyond the stigma; it “is supported on 
each side by sloping sides rising from the upper edge of the 
stigma, in nearly the same manner asin Spiranthes. The sur- 
face of the protuberant part of the rostellum is rough, and 
when dry, can be seen to be formed cf cells; it is delicate and 
when slightly pricked, a little milky viscid fluid exudes; it is 
lined by a layer of very adhesive matter, which sets hard 
quickly when exposed to the air. The protuberant surface of 
the rostellum, when gently rubbed upward (as it would be 
when an insect withdrew its head) is easily removed, and 
carries with it a strip of membrane to the hinder part of which 
the pollen-masses are attached. The sloping sides which sup- 
port the rostellum remain (as in Spiranthes) projecting up like 
a fork and soon wither.” The pollen-masses become attached 
to the back of the rostellum, much as in Spiranthes, and also 
before the flower expands, and the anther-cell “ ultimately 
opens widely, leaving the pollen-masses almost naked but par- 
tially protected within the membranous cup uniting the fila- 
ment or supporting thread of the anther to the edges of the 
stigma. The pollen-grains cohere in packets as in Orchis,” and 
these packets are tied together by strong elastic threads,“ which 
at their upper ends run together and form a single flattened 
brown elastic ribbon, of which the truncated extremity adheres 
to the back of the rostellum. 
“The surface of the orbicular stigma is remarkably viscid, 
which is necessary in order that the unusually strong threads 
connecting the pollen packets should be ruptured. The lip is 
partially divided into two portions; the tip is reflexed, and the 
basal portion is cup-formed and filled with nectar.” Gray, 
speaking of this same species says, “ All freshly opened blos- 
soms have the column so directed—a little bowed forward 
—-that the tip of the disc and of the anther are presented to 
