ine than he was before. Whether this is a deceptive
trick which makes him the more resemble a stone is more than I can
say. I do not remember having seen our eastern toad do it. I have seen
it happen a number of times in the laboratory of a Colorado
naturalist, and it is quite possible that in the open country more
sparsely covered with vegetation than is our ground in the east this
inflating device may serve the toad more effectually than if it kept
its own outline.

Even among creatures far more active than the toad and the katydid an
inconspicuous color must certainly result in distinctly better
protection. Everyone knows the jay and the cardinal when first he has
seen them, if only he has a slight acquaintance with their pictures.
They are so conspicuous that we recognize them at once. More common in
my region than the jay or the cardinal is the red-eyed vireo. This
creature moves industriously in and out among the leaves of our trees.
It is persistently in motion, is nearly constant in song, and is a
bird of fair size, being larger than our English sparrow, though
smaller than a robin. Many a nature lover will recognize twenty-five
or thirty birds at sight without any difficulty, and not know the
vireo. Yet the vireo is more common than two-thirds of the birds he
knows. There can be but one reason for this; the bird is
inconspicuous. The olive-green of its back, with its light under
parts, serves to hide it completely amid the foliage. Even the
bird-lover learns to find it first by its jerky song, and then by
watching for its movements among the leaves.

One aspect of protective coloration has been brought to our attention
by the artist, Mr. Abbott N. Thayer. He first clearly explained why it
is that animals are usually so much lighter on the under side than
they are upon the upper. Mr. Thayer proves his position by taking some
ordinary cobblestones and painting one of them a uniform color and
placing it upon a board painted the same color. One would think the
stone would be inconspicuous; as a matter of fact, is quite easily
seen. The underside of the stone, turned away from the light, is so
shaded as to mark a distinct boundary between the stone and the board.
Another cobblestone was colored on its upper side like the board, but
the color faded into a lighter and lighter tint until the bottom of
the stone was nearly white. This stone, placed upon the board, was at
a short distance nearly invisible. In other wor