Mr.
Wollaston has discovered the remarkable fact that 200 beetles, out
of the 550 species (but more are now known) inhabiting Madeira, are
so far deficient in wings that they cannot fly; and that of the 29
endemic genera no less than 23 have all their species in this
condition! Several facts--namely, that beetles in many parts of the
world are frequently blown out to sea and perish; that the beetles
in Madeira, as observed by Mr. Wollaston, lie much concealed until
the wind lulls and the sun shines; that the proportion of wingless
beetles is larger on the exposed Desertas than in Madeira itself;
and especially the extraordinary fact, so strongly insisted on by
Mr. Wollaston, that certain large groups of beetles, elsewhere
excessively numerous, which absolutely require the use of their
wings are here almost entirely absent;--these several considerations
make me believe that the wingless condition of so many Madeira
beetles is mainly due to the action of natural selection, _combined
probably with disuse_ [italics mine].
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