every organ within him is formed on a different type; as indeed are
those seemingly identical gills, if you come to examine them under
the microscope, having to oxygenate fluids of a very different and
more complicated kind; and, moreover, the Cucumaria's gills were
put round his mouth, the Doris's feathers round the other
extremity; that grey Eolis's, again, are simple clubs, scattered
over his whole back, and in each of his nudibranch congeners these
same gills take some new and fantastic form; in Melibaea those
clubs are covered with warts; in Scyllaea, with tufted bouquets; in
the beautiful Antiopa they are transparent bags; and in many other
English species they take every conceivable form of leaf, tree,
flower, and branch, bedecked with every colour of the rainbow, as
you may see them depicted in Messrs. Alder and Hancock's unrivalled
Monograph on the Nudibranch Mollusca.

And now, worshipper of final causes and the mere useful in nature,
answer but one question, - Why this prodigal variety? All these
Nudibranchs live in much the same way: why would not the same
mould have done for them all? And why, again, (for we must push
the argument a little further,) why have not all the butterflies,
at least all who feed on the same plant, the same markings? Of all
unfathomable triumphs of design, (we can only express ourselves
thus, for honest induction, as Paley so well teaches, allows us to
ascribe such results only to the design of some personal will and
mind,) what surpasses that by which the scales on a butterfly's
wing are arranged to produce a certain pattern of artistic beauty
beyond all painter's skill? What a waste of power, on any
utilitarian theory of nature! And once more, why are those strange
microscopic atomies, the Diatomaceae and Infusoria, which fill
every stagnant pool; which fringe every branch of sea-weed; which