elled shields of the humming-birds, the golden
plumes of the birds of paradise, and the resplendent train of the
peacock. This last exhibits to us the culmination of that marvel and
mystery of animal colour which is so well expressed by a poet-artist in
the following lines. The marvel will ever remain to the sympathetic
student of nature, but I venture to hope that in the preceding chapters
I have succeeded in lifting--if only by one of its corners--the veil of
mystery which has for long shrouded this department of nature.

_On a Peacock's Feather._

In Nature's workshop but a shaving,
Of her poem but a word,
But a tint brushed from her palette,
This feather of a bird!
Yet set it in the sun glance,
Display it in the shine,
Take graver's lens, explore it,
Note filament and line,
Mark amethyst to sapphire,
And sapphire to gold,
And gold to emerald changing
The archetype unfold!
Tone, tint, thread, tissue, texture,
Through every atom scan,
Conforming still, developing,
Obedient to plan.
This but to form a pattern
On the garment of a bird!
What then must be the poem,
This but its lightest word!
Sit before it; ponder o'er it,
'Twill thy mind advantage more,
Than a treatise, than a sermon,
Than a library of lore.

FOOTNOTES:

[Footnote 118: Darwin's _Descent of Man_, p. 271.]

[Footnote 119: Darwin's _Descent of Man_, p. 294, and footnote.]

[Footnote 120: _Nature_, 1871, p. 489.]

[Footnote 121: Darwin in _Nature_, 1880, p. 237.]

[Footnote 122: See the author's _Contributions to Natural Selection_,
chap. vii. in which these facts were first brought forward.]

[Footnote 123: On this point see the author's _Contributions to Natural
Selection_, chap. v. i.]

[Footnote 124: Seebohm's _History of British Birds_, vol. ii.,
introduction, p. xiii.]

[Footnote 125: For details see Darwin's _Descent of Man_, chap. xii.]

[Footnote 126: _Descent of Man_, pp. 417, 418, 420.]

[Footnote 127: _Notes of a Naturalist on the Challenger._]

[Footnote 128: _Descent of Man_, pp. 401, 402.]

[Footnote 129: _Coloration in Animals and Plants_, London, 1886.]

[Footnote 130: _Coloration of Animals_, Pl. X, p. 90; and Pls. II, III,
and IV, pp. 30, 40, 42.]

[Footnote 131: See coloured Fig. in _Proc. Zool. Soc._, 1871, p. 626.]

[Footnote 132: A. Tylor's _Coloration_, p. 40; and Photograph in
Hut