The Wichita daily eagle. [volume] (Wichita, Kan.) 1890-1906, 1892-05-04
PROTECTING COLOR IN ANIMALS.
A Discussion as to What 1t Is That Gives
Mann Greatness Their Cnlnrs

A Discussion as to What 1t Is That Gives
Many Creatures Their Colors-
Where l;chen covered tree stems are COM
mon, we find lichen colored caterpillars,
moths and other insects. A pretty moth
(Cleora glabraria), not uncommon in the
New Forest, is white, busted with black,
and its larva, which feeds upon liehens, is
Of the same color. Some years ago, while
collecting insects in that locality, found
in the same tufts of Gchen a small black
and white spider Just as closely resem bling
the lichens
1t is supposed that these various color
resemb lances have been brought about by
the need for concealment. A caterpillar
frequenting lichens, or bird living among
leaves, would be greatly advantaged by
color resemblance to their several sur
roundings; hence variations in the required
direction have escaped destruction, and
there has been through long ages a grad
ual perfectlng of the reSem blances. This
is the most generally received explanation;
1t accounts also for the coloration of ami
mails like the spider, to which l have re-
ferred, which do not SO much need protec-
ton from their enemies as disguise with
the help of which they can steal upon their
prey.
We must, however, guard against taking
generalities for granted without a careful
examination of the several cases. Many
years ago Messrs. Kirby and Spence called
attention to the resem blance between
ichen feeding insects and their food:
MANY of the notified moths which take
their station of diurnal repose on the north
side of the trunks of trees are with diff
Guilty distinguished from the gray and
green hchens that cover them. OF this
kind are Miselia apriliana and Acronycta
psi. The caterpillar of Bryophila algae,
when it feeds on the yellow Lichen juni-
perinus, is always yellow; but when upon
the gray Lichen saxatilis its hue becomes
gray. This change is probably produced
by the color of its food"
The last sentence contains most note
worthy suggestion, which may help US in
explaining many similar cases of colora-
ton in a much simpler way than by natu-
raj selection or natural elimination 1t Is
well known that the pigments which are
often the cause of the colors in animals, and
always, except in the case of white, of
plants, are extremely resistent to chem
ical action. Some of these pigments will
pass unscathed through the strongest acids
anu the uOSJ powerful dlhdllS- IL Is QIilo
conceivable, then, that they will be equally
unaffected by the chemical action of an ami
mails digestive juices.
There is, however, no need at all for
theory upon this point; it has been shown
to be the case in several instances. DR..
Eisig found in the Mediterranean species
of worm living in the interior of a sponge.
The sponge was brilliant yellow, the
color beng due to particles of a peculiar
pigment deposited in its tissues. The
worm was also yellow, and it might be
supposed that this harmony had been
brought about by the necessity for conceal
ment. An inquisitive fish poking its nose
into the interior of the sponge, in search Of
the various small creatures which con-
stantly take up their lodgings in such
spot, would pass over the ''protectively
colored" worm, and select one that was
obvious on account of it's different colors
1t was found, however, that the color of
the worm was merely due to particles of
the coloring substance of the host, which
had passed out of the intestine of the worm
into its skin.-Blackwood Magazine.