they are even apt to attack the welcome winged visitors. Some 
plants provide honey at flowering time in their leaf axils, which 
serves to feed the horde of useless guests and protect their 
pollen stores far above in the flowers. Again, this is similar to 
our own tactics in dealing with crows and gophers, when we 
supply them with the more easily obtained uncovered grain, 
until the planted grain is too large to be harmed. Smooth, waxy 
stems are another sort of protection, as they make climbing 
difficult. Undoubtedly the deep, cavernous tubes in many 
flowers with their fringed mouths tend to keep out the timid, 
unadventurous type of marauder. For what may not be hidden 
beyond those fringe-like walls in the darkened depths? But 
even those bee visitors that are useful in most cases, may learn 
the ways of a parasitic life, and instead of rendering the usual 
service to their plant acquaintances, they mutilate them by 
biting a hole through the calyx or corolla and secure the honey 
in this less difficult fashion. There are said to be over 300 plants 
in the European flora whose flowers are thus robbed by bumble- 
bees. And in a few cases this robbery threatens their very 
existence. Several species of “Catchfly” in Europe are thus 
afflicted, and because they rarely set seed, they are becoming 
more and more rare. I have often noticed little holes in the 
bell-shaped flowers of some of the wintergreen family, perhaps 
made for the same purpose— illegitimate honey-taking. 
One must bear in mind that many of the devices mentioned 
above have other uses to the plant than those noted, perhaps of 
a totally different character, just as we have windows to see 
through and to let in sunshine, but which also keep out dust and 
cold air. 
The length of life of pollen varies as much as that of the 
various kinds of plants themselves. Pansy pollen is “good” for 
about 26 days, that of the peony for 60 days, while date palm 
pollen has been actually used with excellent results after it was 
ten years old. The Arabs save it from year to }mar as a precau- 
tion against a poor supply or a bad season. It has been said 
that corn, tobacco and date-palm pollen will live for 18 years, 
but this maybe a gardener’s tale. Tomato growers save tomato 
pollen from the summer flowers for use several months later on 
hot-house plants. Pollen of some grape species germinates after 
two months, and that of carnations after at least several weeks. 
Sweet cherry pollen remains alive for 28 days, nasturtium pollen 
for 88 days, while the pollen of some of the grasses dies in a day 
or two. The drier pollen is kept, the longer it lives. Nasturtium 
pollen wetted for 2 minutes and then dried, remained alive for 
two days, as against 88 days for the unwetted sample, while sweet 
cherry pollen in 60 percent humidity was viable for 25 days as 
against 126 days in air absolutely freed from moisture. 
P'lowering plants have many ways in which pollination is 
brought about, and some of these have such a relation to insects, 
snails, and other elements they make use of, as to sound almost 
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