10 OBSERVATIONS ON THE 
recently seen by two observers, Eylandt and Henle, both of whom, however, 
had found them narrower than he. Eylandt, who named them ‘arrectores pili’, 
had never seen more than one bundle connected with each hair-follicle, and 
had failed to detect muscular tissue in the nipple and areola, and in the sub- 
cutaneous cellular tissue of the scrotum, penis, and perineum, where Kolliker 
had described it as existing. Henle had traced the muscles to the most super- 
ficial parts of the dermis, where they divided into numerous little bundles 
1-3000th of aninch in diameter, which could be followed to immediately beneath 
the epidermis ; he had also seen muscular tissue in the nipple, areola, and the 
other parts where Kolliker had described it, but, on the other hand, in the 
opinion of Kélliker, he had gone too far, inasmuch as he described bundles-of 
plain muscular tissue as existing on the exterior of the sudoriferous glands 
and blood-vessels of parts destitute of hairs (such as the palm and sole). These 
K6lliker is unable to discover, and he believes that Henle has been misled by 
the use of boiled preparations, in which, as Henle himself states, fine branches 
of nerves are liable to be mistaken for muscle. Thus it appears that the con- 
firmation furnished by these two observers is by no means a very satisfactory 
one, and that Henle, the only authority on whom we rest for the fact of the 
muscles taking origin immediately beneath the epidermis, cannot, in the opinion 
of Kolliker, be implicitly relied on with reference to this investigation. It 
appears remarkable that Eylandt should have failed to discover muscular 
tissue in the scrotum, for the dartos was long since proved to owe its con- 
tractility to unstriped muscle. Of the parts in question I have examined only 
the areola mammae, which, however, answered well to the description given by 
Kolliker, who states? that the bundles of muscle are there circularly disposed, 
forming a delicate layer in the deeper parts of the corium, and encroaching 
slightly on the subcutaneous cellular tissue. On dissecting a portion of an 
areola from the subcutaneous tissue towards the surface, I found on reaching 
the deepest part of the dermis a delicate reddish-yellow fasciculus circularly 
arranged ; and a portion of this, teased out with needles, and treated with 
acetic acid, presented in a well-marked manner the nuclei of plain muscular 
tissue. A camera-lucida sketch of a small portion is given on a reduced scale 
in PLT Bi Big. - 
In enumerating the parts where he has met with muscles connected with 
the hairs, Kélliker does not mention the scalp, probably because the density 
of the tissue of this part rendered it unfit for investigation by the method in 
which he prepared his objects, viz. isolating a hair-follicle with its sebaceous 
glands and treating it with acetic acid. Its very firmness and consistence, 
? Vide Mikroskopische Anatomie, vol. li, part i, p. 14. 
