LETTER 408. TO W. TURNER.
Down, February 1st [1867].

I thank you cordially for all your full information, and I regret much that
I have given you such great trouble at a period when your time is so much
occupied. But the facts were so valuable to me that I cannot pretend that
I am sorry that I did trouble you; and I am the less so, as from what you
say I hope you may be induced some time to write a full account of all
rudimentary structures in Man: it would be a very curious and interesting
memoir. I shall at present give only a brief abstract of the chief facts
which you have so very kindly communicated to me, and will not touch on
some of the doubtful points. I have received far more information than I
ventured to anticipate. There is one point which has occurred to me, but I
suspect there is nothing in it. If, however, there should be, perhaps you
will let me have a brief note from you, and if I do not hear I will
understand there is nothing in the notion. I have included the down on the
human body and the lanugo on the foetus as a rudimentary representation of
a hairy coat. (408/1. "Descent of Man" I., page 25; II., page 375.) I do
not know whether there is any direct functional connection between the
presence of hair and the panniculus carnosus (408/2. Professor Macalister
draws our attention to the fact that Mr. Darwin uses the term panniculus in
the generalised sense of any sheet of muscle acting on the skin.) (to put
the question under another point of view, is it the primary or aboriginal
function of the panniculus to move the dermal appendages or the skin
itself?); but both are superficial, and would perhaps together become
rudimentary. I was led to think of this by the places (as far as my
ignorance of anatomy has allowed me to judge) of the rudimentary muscular
fasciculi which you specify. Now, some persons can move the skin of their
hairy heads; and is this not effected by the panniculus? How is it with
the eyebrows? You specify the axillae and the front region of the chest