corn by itself, the chances are you would get very few well-filled 
ears. Why? Because the pollen is not heavy enough to fall 
straight down, but descends in a more or less slanting direction, 
so that only a part of the silks of the same plant would be dusted 
with the pollen from its tassel. Then again, much of the pollen 
might be shed before the silks appear. And curiously enough, 
corn offspring from the same plant acting as father and mother, 
is not apt to be as robust or as prolific as those with two distinct 
plant parents. 
Some flowers, or rather flower clusters, strictly speaking, 
have about as disgusting an odor as there is in all the range of 
scents. All lovers of wild things know the skunk cabbage and its 
fetid perfume. But it has many relations in the tropics with per- 
fumes not differing in kind, but untold times more powerful. One 
of these is sometimes found in conservatories under the name of 
black calla lily, and on a hot day its fetid odor permeates the 
whole structure. One wonders perhaps why a plant exists with 
such a vile characteristic. But remember that plants are “look- 
ing out ” for themselves and are quite oblivious to the tastes of 
human beings. This odor is an “ at home ’’ invitation to certain 
kinds of flies that revel in just this kind of an atmosphere. And 
these flies are invited to a nice, warm, barrel-shaped chamber in 
the base of the so-called flower— a chamber with a row of down- 
ward-pointing bristles for a gate, through which they easily enter, 
but through which they cannot make their exit until the flower 
has achieved its purpose. The food is plentiful, and after several 
days, when the pollen has been discharged and the flies have been 
dusted with it, the gate of bristles becomes limp, dries up, and 
they are at liberty to pass on to the next flower cluster, where 
they cannot help but dust its receptive pistils. To some of these 
arums, as the family is called, come numerous little flies or midges, 
and in one species the small visitors, after their usefulness 
as pollinators has passed, are entangled by the sticky hairs and 
digested by plant juices. Other flowers of this family attract 
more gaudy visitors — big green-gilded carrion flies, some of which 
even raise their families in the flower’s odorous depths. Still 
other species attract the carrion beetles, as many as 250 individuals 
having been taken from one single spathe or “flower.” One of 
these arums, living in southeastern Asia, attracts snails by an 
odor issuing from an entrance to the female flowers. The snails, 
already covered with pollen from other flowers, crawl through 
this door which soon closes, and do their Fate’s appointed task 
of pollinating these female flowers. But the road they have 
traveled has a gruesome end, for after performing this service, 
the plant to protect itself against the flower-eating depredations 
of its servants, secretes a caustic poisonous liquid in which the 
snails die. As a student of natural selection, I have grave 
doubts about this tale. Through the centuries in which this 
tragedy has repeated itself, it would seem that the supply of 
snails thus tempted would have failed unless perhaps they take 
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