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146 ANATOMY. ;

forming plexuses of fine nerve-fibres near the surface. From the
most superficial of these plexuses, or those situated immediately below
tlie epidermis/ fine non-medullated nerve-fibres pass upward between
the cylindrical cells of the stratum Malpighii of the cuticle, where they
terminate. The nerves are abundantly distributed to parts that are
covered with hair, especially where such hair is used as a sentient organ,
as is the case with the whiskers of the cat. The termination of many
of the nerves will be found in the tactile and Pacinian corpuscles.
The Tactile or Touch Corpuscles (Figs. 72, 73) are usually oval in
Fig 72

Fig. 73.

Fp

Section of .Skin, sliowing two PajjilUe and deei)er layers of Tactile Corpuscle within a papil-
Epidermis: o, vascular papilla with capillary loop passing la of the skm of the hand,
from subjacent vessel, c ; b, nerve-papilla with tactile cor- stained with chloride of gold.
puscle, t (the latter exhibits transverse fibrous markings) The convolutions of the nerve-
d, nerve passing up to it; /, /, sections of spirally winding fibres within the corpuscle are
nerve-fibres. seen. is);, epidermis.
shape—they may be straight or slightly folded—and are situated within
certain of the papillae of the corium ; they are attached to medullary
nerve-fibres. These papillfe contain no blood-vessels, and are called
tactile or sensory, in contradistinction to the vascular papillae which
contain the blood-vessels. Their number varies according to location,
they being most numerous where the touch is mofst acute, as on the
inner or palmar side of the last phalanges of the fingers.
The Pacinian Corpuscles are oval or olive-shaped bodies, receiving
the terminal ends of cutaneous nerves. In the skin they are situated
in the subcutaneous connective tissue, and like the touch-corpuscles are
most abundant on the palms of the hands, soles of the feet, the fingers
and toes, and more especially on their distal phalanges.
Pigment.—The color of the skin depends upon the deposit of pig-
ment-granules. This is generally found in the lowest .stratum of the
' The lymphatics do not pass into the epidenn, and that is the reason normal skin is
not an al)sorbin