White, crimson, emerald green, shining golden yellow, are amongst the
colors seen in the eyes of birds. In owls, herons, cormorants, and
many other tribes, the brightly-tinted eye is incomparably the finest
feature and chief glory. It fixes the attention at once, appearing like
a splendid gem, for which the airy bird-body with its graceful curves
and soft tints forms an appropriate setting. When the eye closes in
death, the bird, except to the naturalist, becomes a mere bundle of
dead feathers: crystal globes may be put into the empty sockets, and
a bold life-imitating attitude given to the stuffed specimen; but the
vitreous orbs shoot forth no life-like flames, the “passion and the
fire whose fountains are within” have vanished, and the best work of
the taxidermist, who has given a life to his bastard art, produces
in the mind only sensations of irritation and disgust. In museums,
where limited space stands in the way of any abortive attempts at
copying nature too closely, the stuffer’s work is endurable because
useful; but in a drawing-room, who does not close his eyes or turn
aside to avoid seeing a case of stuffed birds—those unlovely mementoes
of death in their gay plumes? who does not shudder, albeit not with
fear, to see the wild cat, filled with straw, yawning horribly, and
trying to frighten the spectator with its crockery glare? I shall
never forget the first sight I had of the late Mr. Gould’s collection
of humming-birds (now in the National Museum), shown to me by the
naturalist himself, who evidently took considerable pride in the work
of his hands. I had just left tropical nature behind me across the
Atlantic, and the unexpected meeting with a transcript of it in a
dusty room in Bedford Square gave me quite a shock. Those pellets of
dead feathers, which had long ceased to sparkle and shine, stuck with
wires—not invisible—over blossoming cloth and tinsel bushes, how
melancholy they made me feel!
Considering the bright color and great splendor of some eyes,
particularly in birds, it seems probable that in these cases the organ
has a twofold use: first and chiefly, to see; secondly, to intimidate
an adversary with those luminous mirrors, in which all the dangerous
fury of a creature brought to bay is best depicted. Throughout nature
the dark eye predominates; and there is certainly a great depth of
fierceness in the dark eye of a bird of prey; but its effect is less
than that produced by the vividly-colored eye, or even of the white
eye of some raptorial species, as, for instance, of the Asturina
pucherani. Violent emotions are associated in our minds—possibly,
also, in the minds of other species—with certain colors. Bright red
seems the appropriate hue of anger: the poet Herbert even calls the
rose “angrie and brave” on account of its hue: and the red or orange
certainly expresses resentment better than the dark eye. Even a very
slight spontaneous variation in the coloring of the irides might give
an advantage to an individual for natural selection to act on; for we
can see in almost any living creature that not only in its perpetual
metaphorical struggle for existence is its life safeguarded in many
ways; but when protective resemblances, flight, and instincts of
concealment all fail, and it is compelled to engage in a real struggle
with a living adversary, it is provided for such occasions with another
set of defences. Language and attitudes of defiance come into play;
feathers or hairs are erected; beaks snap and strike, or teeth are
gnashed, and the mouth foams or spits; the body puffs out; wings are
waved or feet stamped on the ground, and many other gestures of rage
are practised. It is not possible to believe that the coloring of the
crystal globes, towards which an opponent’s sight is first directed,
and which most vividly exhibit the raging emotions within, can have
been entirely neglected as a means of defence by the principle of
selection in nature. For all these reasons I believe the bright-colored
eye is an improvement on the dark eye.
Man has been very little improved in this direction, the dark eye,
except in the north of Europe, having been, until recent times,
almost or quite universal. The blue eye does not seem to have any
advantage for man in a state of nature, being mild where fierceness
of expression is required; it is almost unknown amongst the inferior
creatures; and only on the supposition that the appearance of the
eye is less important to man’s welfare than it is to that of other
species can we account for its survival in a branch of the human race.
Little, however, as the human eye has changed, assuming it to have
been dark originally, there is a great deal of spontaneous variation
in individuals, light hazel and blue-grey being apparently the most
variable. I have found curiously marked and spotted eyes not uncommon;
in some instances the spots being so black, round, and large as to
produce the appearance of eyes with clusters of pupils on them. I have
known one person with large brown spots on light blue-grey eyes, whose
children all inherited the peculiarity; also another with reddish hazel
irides thickly marked with fine characters resembling Greek letters.
This person was an Argentine of Spanish blood, and was called by his
neighbors _ojos escritos_, or written eyes. It struck me as a very
curious circumstance that these eyes, both in their ground color and
the form and disposition of the markings traced on them, were precisely
like the eyes of a common species of grebe, _Podiceps rollandi_. But
we look in vain amongst men for the splendid crimson, flaming yellow,
or startling white orbs which would have made the dark-skinned brave
inspired by violent emotions a being terrible to see. Nature has
neglected man in this respect, and it is to remedy the omission that he
stains his face with bright pigments and crowns his head with eagles’
barred plumes.
Bright-colored eyes in many species are probably due, like ornaments
and gaudy plumage, to sexual selection. The quality of shining in the
dark, however, possessed by many nocturnal and semi-nocturnal species,
has always, I believe, a hostile purpose. When found in inoffensive
species, as, for instance, in the lemurs, it can only be attributed to
mimicry, and this would be a parallel case with butterflies mimicking
the brilliant “warning colors” of other species on which birds do not
prey. Cats amongst mammals, and owls amongst birds, have been most
highly favored; but to the owls the palm must be given. The feline
eyes, as of a puma or wild cat, blazing with wrath, are wonderful to
see; sometimes the sight of them affects one like an electric shock;
but for intense brilliance and quick changes, the dark orbs kindling
with the startling suddenness of a cloud illuminated by flashes of
lightning, the yellow globes of the owl are unparalleled. Some readers
might think my language exaggerated. Descriptions of bright sunsets and
of storms with thunder and lightning would, no doubt, sound extravagant
to one who had never witnessed these phenomena. Those only who spend
years “conversing with wild animals in desert places,” to quote Azara’s
words, know that, as with the atmosphere, so with animal life, there
are special moments; and that a creature presenting a very sorry
appearance dead in a museum, or living in captivity, may, when hard
pressed and fighting for life in its own fastness, be sublimed by its
fury into a weird and terrible object.
Nature has many surprises for those who wait on her: one of the
greatest she ever favored me with was the sight of a wounded Magellanic
eagle-owl I shot on the Rio Negro in Patagonia. The haunt of this bird
was an island in the river, overgrown with giant grasses and tall
willows, leafless now, for it was in the middle of winter. Here I
sought for and found him waiting on his perch for the sun to set. He
eyed me so calmly when I aimed my gun, I scarcely had the heart to pull
the trigger. He had reigned there so long, the feudal tyrant of that
remote wilderness? Many a water-rat, stealing like a shadow along the
margin between the deep stream and the giant rushes, he had snatched
away to death; many a spotted wild pigeon had woke on its perch at
night with his cruel crooked talons piercing its flesh; and beyond the
valley on the bushy uplands many a crested tinamou had been slain on
her nest and her beautiful glossy dark green eggs left to grow pale in
the sun and wind, the little lives that were in them dead because of
their mother’s death. But I wanted that bird badly, and hardened my
heart: the “demoniacal laughter” with which he had so often answered
the rushing sound of the swift black river at eventide would be heard
no more. I fired: he swerved on his perch, remained suspended for a
few moments, then slowly fluttered down. Behind the spot where he had
fallen was a great mass of tangled dark-green grass, out of which rose
the tall, slender boles of the trees; overhead through the fretwork
of leafless twigs the sky was flushed with tender roseate tints, for
the sun had now gone down and the surface of the earth was in shadow.
There, in such a scene, and with the wintry quiet of the desert over
it all, I found my victim stung by his wounds to fury and prepared for
the last supreme effort. Even in repose he is a big eagle-like bird:
now his appearance was quite altered, and in the dim, uncertain light
he looked gigantic in size—a monster of strange form and terrible
aspect. Each particular feather stood out on end, the tawny barred
tail spread out like a fan, the immense tiger-colored wings wide open
and rigid, so that as the bird, that had clutched the grass with his
great feathered claws, swayed his body slowly from side to side—just
as a snake about to strike sways its head, or as an angry watchful cat
moves its tail—first the tip of one, then of the other wing touched
the ground. The black horns stood erect, while in the centre of the
wheel-shaped head the beak snapped incessantly, producing a sound
resembling the clicking of a sewing-machine. This was a suitable
setting for the pair of magnificent furious eyes, on which I gazed with
a kind of fascination, not unmixed with fear when I remembered the
agony of pain suffered on former occasions from sharp, crooked talons
driven into me to the bone. The irides were of a bright orange color,
but every time I attempted to approach the bird they kindled into great
globes of quivering yellow flame, the black pupils being surrounded by
a scintillating crimson light which threw out minute yellow sparks into
the air. When I retired from the bird this preternatural fiery aspect
would instantly vanish.
The dragon eyes of that Magellanic owl haunt me till now, and when I
remember them, the bird’s death still weighs on my conscience, albeit
by killing it I bestowed on it that dusty immortality which is the
portion of stuffed specimens in a museum.
The question as to the cause of this fiery scintillating appearance
is, doubtless, one very hard to answer, but it will force itself on
the mind. When experimenting on the bird, I particularly noticed that
every time I retired the nictitating membrane would immediately cover
the eyes and obscure them for some time, as they will when an owl is
confronted with strong sunlight; and this gave me the impression that
the fiery, flashing appearance was accompanied with, or followed by,
a burning or smarting sensation. I will here quote a very suggestive
passage from a letter on this subject written to me by a gentleman
of great attainments in science: “Eyes certainly do shine in the
dark—some eyes, _e.g._ those of cats and owls; and the scintillation
you speak of is probably another form of the phenomenon. It probably
depends upon some extra-sensibility of the retina analogous to what
exists in the molecular constitution of sulphide of calcium and other
phosphorescent substances. The difficulty is in the _scintillation_.
We know that light of this character has its source in the heat
vibrations of molecules at the temperature of incandescence, and the
electric light is no exception to the rule. A possible explanation is
that supra-sensitive retinæ in times of excitement become increasedly
phosphorescent, and the same excitement causes a change in the
curvature of the lens, so that the light is focussed, and _pro tanto_
brightened into sparks. Seeing how little we know of natural forces, it
may be that what we call light in such a case is eye speaking to eye—an
emanation from the window of one brain into the window of another.”
The theory here suggested that the fiery appearance is only another
form of the phosphorescent light found in some eyes, if correct,
would go far towards disposing of all those cases one hears and reads
about—some historical ones—of human eyes flashing fire and blazing with
wrath. Probably all such descriptions are merely poetic exaggerations.
One would not look for these fiery eyes amongst the peaceful children
of civilization, who, when they make war, do so without anger, and
kill their enemies by machinery, without even seeing them; but amongst
savage or semi-savage men, carnivorous in their diet, fierce in
disposition, and extremely violent in their passions. It is precisely
amongst people of this description that I have lived a great deal. I
have often seen them frenzied with excitement, their faces white as
ashes, hair erect, and eyes dropping great tears of rage, but I have
never seen anything in them even approaching to that fiery appearance
described in the owl.
Nature has done comparatively little for the human eye, not only in
denying it the terrifying splendors found in some other species, but
also in the minor merit of beauty; yet here, when we consider how much
sexual selection concerns itself with the eye, a great deal might have
been expected. When going about the world one cannot help thinking
that the various races and tribes of men, differing in the color of
their skins and in the climates and conditions they live in, ought to
have differently colored eyes. In Brazil, I was greatly struck with
the magnificent appearance of many of the negro women I saw there:
well-formed, tall, majestic creatures, often appropriately clothed in
loose white gowns and white turban-like headdresses; while on their
round polished blue-black arms they wore silver armlets. It seemed to
me that the pale golden irides, as in the intensely black tyrant-bird
Lichenops, would have given a finishing glory to these sable beauties,
completing their strange unique loveliness. Again, in that exquisite
type of female beauty which we see in the white girl with a slight
infusion of negro blood, giving the graceful frizzle to the hair,
the purple-red hue to the lips, and the dusky terra-cotta tinge to
the skin, an eye more suitable than the dark dull brown would have
been the intense orange brown seen in the lemur’s eye. For many very
dark-skinned tribes nothing more beautiful than the ruby-red iris could
be imagined; while sea-green eyes would have best suited dusky-pale
Polynesians and languid peaceful tribes like that one described in
Tennyson’s poem:—
And round about the keel with faces pale,
Dark faces pale against that rosy flame,
The mild-eyed melancholy Lotos-eaters came.
Since we cannot have the eyes we should like best to have, let us
consider those that nature has given us. The incomparable beauty of the
“emerald eye” has been greatly praised by the poets, particularly by
those of Spain. Emerald eyes, if they only existed, would certainly be
beautiful beyond all others, especially if set off with dark or black
hair and that dim pensive creamy pallor of the skin frequently seen in
warm climates, and which is more beautiful than the rosy complexion
prevalent in northern regions, though not so lasting. But either they
do not exist or else I have been very unfortunate, for after long
seeking I am compelled to confess that never yet have I been gratified
by the sight of emerald eyes. I have seen eyes _called_ green, that
is, eyes with a greenish tinge or light in them, but they were not
the eyes I sought. One can easily forgive the poets their misleading
descriptions, since they are not trustworthy guides, and very often,
like Humpty Dumpty in “Through the Looking Glass,” make words do “extra
work.” For sober fact one is accustomed to look to men of science;
yet, strange to say, while these complain that we—the unscientific
ones—are without any settled and correct ideas about the color of our
own eyes, they have endorsed the poet’s fable, and have even taken
considerable pains to persuade the world of its truth. Dr. Paul Broca
is their greatest authority. In his “Manual for Anthropologists” he
divides human eyes into four distinct types—orange, green, blue,
grey; and these four again into five varieties each. The symmetry of
such a classification suggests at once that it is an arbitrary one.
Why orange, for instance? Light hazel, clay color, red, dull brown,
cannot properly be called orange; but the division requires the five
supposed varieties of the dark pigmented eye to be grouped under one
name, and because there is yellow pigment in some dark eyes they are
all called orange. Again, to make the five grey varieties the lightest
grey is made so light that only when placed on a sheet of white paper
does it show grey at all: but there is always some color in the human
skin, so that Broca’s eye would appear absolutely white by contrast—a
thing unheard of in nature. Then we have green, beginning with the
palest sage green, and up through grass green and emerald green, to the
deepest sea green and the green of the holly leaf. Do such eyes exist
in nature? In theory they do. The blue eye is blue, and the grey grey,
because in such eyes there is no yellow or brown pigment on the outer
surface of the iris to prevent the dark purple pigment—the _uvea_—on
the inner surface from being seen through the membrane, which has
different degrees of opacity, making the eye appear grey, light or dark
blue, or purple, as the case may be. When yellow pigment is deposited
in small quantity on the outer membrane, then it should, according to
the theory, blend with the inner blue and make green. Unfortunately
for the anthropologists, it doesn’t. It only gives in some cases the
greenish variable tinge I have mentioned, but nothing approaching to
the decided greens of Broca’s tables. Given an eye with the right
degree of translucency in the membrane and a very thin deposit of
yellow pigment spread equally over the surface; the result would be a
perfectly green iris. Nature, however, does not proceed quite in this
way. The yellow pigment varies greatly in hue; it is muddy yellow,
brown, or earthy color, and it never spreads itself uniformly over the
surface, but occurs in patches grouped about the pupil and spreads in
dull rays or lines and spots, so that the eye which science says “ought
to be called green” is usually a very dull blue-grey or brownish-blue,
or clay color, and in some rare instances shows a changeable greenish
hue.
In the remarks accompanying the report of the Anthropomentric Committee
of the British Association for 1881 and 1883, it is said that green
eyes are more common than the tables indicate, and that eyes that
should properly be called green, owing to the popular prejudice
against that term, have been recorded as grey or some other color.
Does any such prejudice exist? or is it necessary to go about with the
open manual in our hands to know a green eye when we see one? No doubt
the “popular prejudice” is supposed to have its origin in Shakespeare’s
description of jealousy as a green-eyed monster; but if Shakespeare has
any great weight with the popular mind the prejudice ought to be the
other way, since he is one of those who sing the splendors of the green
eye.