me I., page 351, for F. Muller's observations; and for
a reference to Landois' paper.) I have often reflected with surprise on
the diversity of the means for producing music with insects, and still
more with birds. We thus get a high idea of the importance of song in
the animal kingdom. Please to tell me where I can find any account of
the auditory organs in the orthoptera? Your facts are quite new to me.
Scudder has described an annectant insect in Devonian strata, furnished
with a stridulating apparatus. (446/3. The insect is no doubt Xenoneura
antiquorum, from the Devonian rocks of New Brunswick. Scudder compared
a peculiar feature in the wing of this species to the stridulating
apparatus of the Locustariae, but afterwards stated that he had been led
astray in his original description, and that there was no evidence in
support of the comparison with a stridulating organ. See the "Devonian
Insects of New Brunswick," reprinted in S.H. Scudder's "Fossil Insects
of N. America," Volume I., page 179, New York, 1890.) I believe he is to
be trusted, and if so the apparatus is of astonishing antiquity. After
reading Landois' paper I have been working at the stridulating organ in
the lamellicorn beetles, in expectation of finding it sexual, but I have
only found it as yet in two cases, and in these it was equally developed
in both sexes. I wish you would look at any of your common lamellicorns
and take hold of both males and females and observe whether they make
the squeaking or grating noise equally. If they do not, you could
perhaps send me a male and female in a light little box. How curious
it is that there should be a special organ for an object apparently so
unimportant as squeaking. Here is another point: have you any Toucans?
if so, ask any trustworthy hunter whether the beaks of the males, or of
both sexes, are more brightly coloured during the breeding season than
at other times of the year? I have also to thank you for a previous
letter of April 3rd, with some interesting facts on the variation of
maize, the sterility of Bignonia and on conspicuous seeds. Heaven knows
whether I shall ever live to make use of half the valuable facts which
you have communicated to me...

LETTER 447. TO J. JENNER WEIR. Down, June 18th [1868].

Many thanks. I am glad that you mentioned the linnet, for I had much
difficulty in persuading myself that the crimson breast could be due to
change in the old feathers, as the books say. I am g