t
when motionless they cannot be discerned. Some butterflies
resemble dead, dry or decaying leaves so closely as to elude
discovery. Every individual better protected by colour than
others, has a better chance for life, and of transmitting his
hues. Harmless beetles and flies are so like wasps and bees
as to be left alone. 71

HUXLEY, THOMAS H.

EVOLUTION OF THE HORSE

The hoof of the horse is simply a greatly enlarged and
thickened nail: four of his five toes are reduced to mere
vestiges. His teeth are built of substances of varying
hardness: they wear away at different rates presenting uneven
grinding surfaces. Probable descent of the horse, link by
link, especially as traced in the fossils of North America.
Evolution has taken a long time: how long the physicist and
the astronomer must decide. 101

HOWARD, LELAND O.

FIGHTING PESTS WITH INSECT ALLIES

A scale insect threatened with ruin the orchards of California.
Professor C. V. Riley decided that the pest was a native
of Australia. Mr. A. Hoebele observes in Australia that
the pest is kept down by ladybirds. These are accordingly
sent to California where they destroy the scale insect and
restore prosperity among the fruit-growers. Another pest,
of olive trees, is devoured by an imported ladybird of
another species. This plan extended to Portugal and Egypt
with success. Grasshoppers killed by a fungus cultivated
for the purpose. Introduction into the United States of
the insect which fertilizes the Smyrna fig. 123

ILES, GEORGE

THE STRANGE STORY OF THE FLOWERS: A CHAPTER IN MODERN BOTANY

Dress is important, whether natural or artificial. Because
they catch dust on their clothes, bees, moths and butterflies
have brought about myriad espousals of flower with flower.
Colours and scents of blossoms attract insects. A flower
which in form, scent or hue varies gainfully is likely to
survive while others perish. All the parts of a flower are
leaves in disguise. Floral modes of repulsion and defence.
Plants which devour insects, a habit gradually acquired. The
mesquit tree tells of water. Plants believed to indicate
mineral veins. Seeds as emigrants equipped with wings or