14 OBSERVATIONS ON THE MUSCULAR TISSUE OF THE SKIN 
average diameter is, according to my experience, I-200th of an inch, which 
is less than half the average of Kolliker’s measurements, but this discrepancy 
is probably due to difference of situation in the parts observed, Kolliker not 
having examined the scalp: for one muscle which I sketched from the pubes 
was very nearly 1-r1ooth of an inch in diameter. 
With regard to the statement of Henle, that muscular tissue exists in parts 
destitute of hairs, I have searched with diligence many good sections of both 
the palm and the sole, without having been able to discover any evidence of 
it on the exterior of either the sudoriferous glands or blood-vessels of these 
parts. In a section treated with acetic acid, the elongated nuclei of the internal 
coat of a small blood-vessel sometimes give it an appearance that might at 
first sight be mistaken for that of unstriped muscle; but this is an error 
easily avoided by care, and I cannot but agree with Kolliker in thinking that, 
in some way or other, his boiled preparations have led Henle into error. 
In order to verify Kolliker’s statement? that no unstriped muscle exists 
in connexion with the vibrissae of mammalia, I examined the feelers of a cat. 
These large hairs extend far down into the tissues beneath the skin, and have 
a more complex muscular apparatus than the small hairs of the human skin. 
Bundles of muscles extend from the lower part of the gigantic hair-follicle 
obliquely upwards to the inferior aspect of the skin, and, in addition to these, 
there is muscle surrounding the large nerve that enters the base of each hair- 
follicle. These muscles were all of the striped kind, but extremely soft and 
extensile, and among the fibres were a number of very elongated nuclei, but 
I saw no distinct evidence of the admixture of unstriped muscle. 
In conclusion, I may state that this investigation has proved to me the 
general correctness of Kolliker’s original observations, and also of the results 
of Henle’s further inquiry, except in the case of the alleged muscularity of 
parts destitute of hairs; and I shall be happy if the little additional matter 
communicated in this paper shall be found to bear as well the scrutiny of others. 
University College Hospital, June 1, 1853. 
* Vide Mikroskopische Anatomie, vol. ii, part i, p. 15. 
