238 THE FLORAL WORLD AND GARDEN GUIDE. 
In the single flower (Fig. 2) we observe the plan upon which 
all orchids are fashioned, the number three ruling the plant, 
however modified by the Creator, ‘‘ for whose pleasure they are and 
were created.” Three sepals, three petals, three pistils, and twice 
three stamens. These are not discernible at first, because the 
large lower petal, or labellum, is so prominent, and two upper petals 
are joined together, and one of the sepals adhere to them so closely 
as to require particular attention. 
Of the three pistils, one is modified into a rostellum or beak, + ; 
the other two are confluent, and form a cup, the surface of which 
is the stigma. This stigmatic surface, s, like all other ‘stigmas, 
becomes at a particular moment highly viscid, attracting and retain- 
ing the pollen grains, which throw their granular tubes down the 
loosened tissue, to fructify the ovules in the ovary beneath, o. 
Six stamens, according to Lindley and Hooker, are discoverable 
in the perfect orchis; only one fertile anther is apparent in 
Spiranthes, which now demands close attention. 
In examining a young Neottia with a pocket lens, and looking 
into the flower, we observe two pale yellow spots in the throat; 
these are the pollen masses or pollinia lying under the anther cell, 
a, and immediately over the stigma, s, attached to the rostellum, 7, 
by a boat-shaped disk, in such a position as to render it highly 
improbable that the pollen grains of that flower can ever touch their 
own stigma. If a needle is passed into the flower, and this disk 
touched lightly, it will detach itself, and with it the whole pollinia, 
as in Fig. 5. 
This, on being pressed between thin glass under the microscope, 
will show the square or oblong pollen grains (Fig. 6); or if applied 
to the stigmatic surface of an older flower, these bright golden grains - 
will adhere to the glistening green cup, and be a beautiful object 
under a low power. 
Some flowers, if stripped of sepals and petals, as in Fig. 4, will 
show the anther cell empty, the stigma untouched, the flower 
unfructified—where, then, is the pollinia ? 
This is Darwin’s discovery, that Spiranthes, like so many of 
its brethren, is indebted to insect visitors for the perfection of its 
seed, depending also on the movement of its labellum, which at 
one period closes the throat, and protects the young stigma until 
its hour of maturity has arrived, then drops slowly down, opening 
its honey glands to invite the wandering bee, which bears upon 
its proboscis the pollinia previously extracted from a younger 
flower. 
Resting on the sunny hills above Torquay, Darwin watched the 
intercourse between insect and flower. The little Neottia giving 
forth a sweet perfume to attract the living “ winged things.” “He 
saw the humble bee, as I have seen the hovering Syrphide and 
Tipule, and small Hymenoptera enter the flower cup; but these 
only entered one flower, and then flew away, I know not whither. 
Whereas he saw the bee always alight at the bottom of the spike, 
and, climbing up regularly, withdraw the pollinia from the upper 
and youngest flower, then fly to a next plant, rest for a moment on 
