have
additional protection. This they at once obtain by acquiring a
resemblance to other species which, from whatever cause, enjoy a
comparative immunity from persecution."

[55] This no doubt refers to Janet's "Materialisme Contemporain."

[56] _Quarterly Journal of Science_, January 7, 1867. "Ice Marks in
North Wales," by A.R. Wallace.

[57] I.e., the suggestion that conspicuous caterpillars or perfect
insects (e.g. white butterflies) which are distasteful to birds are
protected by being easily recognised and avoided.

[58] A bearded woman having an irregular double set of teeth. See
"Animals and Plants," ii. 328.

[59] The letter to which this is a reply is missing. It evidently refers
to Wallace's belief in the paramount importance of protection in the
evolution of colour. _See also_ Darwin's letter of February 26, 1867.

[60] _Menura superba._ See "The Descent of Man" (1901), p. 687.
Rhynchaea, mentioned on p. 184, is discussed in the "Descent," p. 727.
The female is more brightly coloured than the male and has a convoluted
trachea, elsewhere a masculine character. There seems some reason to
suppose that "the male undertakes the duty of incubation."

[61] _Westminster Review_, July, 1867.

[62] _Angraecum sesquipedale_, a Madagascar orchid, with a whip-like
nectary, 11 to 12 in. in length, which, according to Darwin
("Fertilisation of Orchids," 2nd Edit., p. 163), is adapted to the
visits of a moth with a proboscis of corresponding length. He points out
that there is no difficulty in believing in the existence of such a moth
as F. Mueller had described (_Nature_, 1873, p. 223), a Brazilian
sphinx-moth with a trunk 10 to 11 in. in length. Moreover, Forbes had
given evidence to show that such an insect does exist in Madagascar
(_Nature_, 1873, p. 121). The case of _Angraecum_ was put forward by the
Duke of Argyll as being necessarily due to the personal contrivance of
the Deity. Mr. Wallace shows (p. 476, _Quarterly Journal of Science_,
1867) that both proboscis and nectary might be increased in length by
means of Natural Selection. It may be added that Hermann Mueller has
shown good grounds for believing that mutual specialisation of this kind
is beneficial both to insect and to plant.

[63] "Variation of Animals and Plants," 1st Edit., ii. 431. "Did He
cause the frame and mental qualities of the dog to vary in order that a
breed might be formed of indomitable ferocity, with jaws fitted to pin
down the b