256 AGENCY OF INSECTS 
tube, without touching the stigma at all. Sometimes 
they went in the tube as first described, and then slipped 
out at the side instead of backing out. Several went on 
top of the flower and tried to find other ways to get at the 
sweets below, but in every instance they failed, and soon 
left that position. 
At the Botanical Garden, Cambridge, Mass., I noticed 
bees on several foreign species of Iris, in some of which, 
as Iris pseudocarus of Southern Europe, the tube is more 
nearly perfect, so that it is impossible for them to find a 
side entrance or egress. 
The corolla of Andromeda floribunda Pursh, is nearly 
urn-shaped, hanging with the open end or entrance down. 
The ten long anthers open at the apex by two round 
holes, and each anther is supplied with two horizontal 
or reflexed awns on the outside next the corolla. The 
stigma is just at the narrow mouth of the corolla. . Bees 
in abundance visit the flowers, thrusting their long tongue 
or proboscis against the awns or horns of the anther, as 
they reach in for nectar which is secreted farther on. By 
hitting the awns the anthers are disturbed, and the holes 
brought close against some part of the bee’s probos- 
cis, which is well sprinkled over with pollen, as well as 
the other mouth parts hanging below the flower. Bees 
were examined, and found to have the parts mentioned 
covered with the four-grained pollen which is peculiar to 
a few plants. 
I cannot see how pollen alights on the stigmas of this 
plant, for in falling out in the natural way it must pass by 
to the ground. But the insect puts the material in place 
every time as effectually as a mason can stick mortar on 
the ceiling of a room. The Blueberry ( Vaccinium) is 
similar in structure to the Andromeda, except that the 
