incredible. I have no doubt that were I to relate some of them 
in a striking enough manner, and with the proper facial expres- 
sion, my hearers would put me down as a nature faker. In the 
first place, the best interests of plants in general demand cross- 
fertilization or cross-pollination— that their seed should be the 
product of the union of pollen and eggs from different plants — 
in other words, the fathers should not be too near kin, even 
though most plants have both the father and mother elements in 
the same flower. The mingling of two different family lines tends 
to produce more vigorous and adaptable offspring, by bringing 
about the opportunity for two different sets of hereditary char- 
acters to be shuffled, card-game fashion, and thus form new 
combinations. So general is the plant’s desire to prevent 
inbreeding that Darwin has said: “ Nature abhors self-fertiliza- 
tion.” Though in many cases, one must remember, that the 
plant has not yet experimented enough to prevent it. Of the 
many ways that plants preclude this, some of the more striking 
are self-sterility, or the incompatibility of the pollen and the 
pistil; dioeciousness, the separation of the two sexes in different 
flowers on separate plants; monoeciousness, or the separation 
of the two sexes in different flowers on the same plant; pro- 
terandery, the shedding of the pollen before the pistil of the 
same plant or flower is ready to receive it ; and numerous special 
contrivances that prevent the pollen generally from being used 
on the flowers of the same plant. 
Self-sterility is common among the poppies, the muscadine 
table grapes of the south, many tropical fruits, some varieties of 
flowering tobaccos, and numerous -wild plants, Among ph ms 
the Green Gage, Grand Duke, Coe’s Golden Drop, and Prune 
d’Agen produce no fruit if pollinated with their own pollen. 
Such apples as the Northern Greening and Cox’s Orange Pippin 
remain barren if dependant on themselves for fertilization. In 
the case of cherries, the Black Tartarian, Black Heart, White 
Heart and Early Rivers, pass a fruitless existence unless planted 
so that the wind or bees or other insects can bring pollen from 
other varieties of cherries to their waiting pistils. Twenty-five 
years or more ago, great pear orchards of one variety, such as 
the Kieffer or the LeConte, were planted in the South, and at the 
proper age they blossomed profusely but remained pearless. 
Their owners sought our national agricultural department experts 
for aid and the discovery that these varieties were self-sterile 
was made. Trees of other varieties were planted in their midst 
and they ceased to be barren. 
But even in these orchards of mixed varieties, barrenness 
would still have been the dominant note if it were not for the 
bees and other insects that go from flower to flower and from 
tree to tree gathering honey and distributing, unintentionally, of 
course, the precious pollen dust. Did it ever occur to any of you 
what a calamnity it would be if all the bees, wasps, moths, 
butterflies and flies of the whole world, through some strange 
7 
