Hooper, Robert [Editor]: The Anatomist's Vade-Mecum: Containing The Anatomy, Physiology, Morbid Appearances, &c. Of The Human Body ; The Art of making Anatomical Preparations, &c. To which are added Anatomical, Physiological, Medical, And Surgical Examinations For Students (London, 1811)

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They arc covered by a membrane, called perichondrium,
which serves the same purposes as periosteum does to bone.
The diseases of cartilages are little if at all understood.

PERIOSTEUM.

A membrane which invests the external surface of all the
bones except the crowns of the teeth.

Names. Vericranium, on the cranium; periorbita, on the
orbits; perichondrium, when it covers cartilages ; and pcrides-
mium, when it covers ligaments.

Substance. Fibrous, furnished with arteries, veins, nerves,
ami absorbent vessels.

Connexion. The periosteum coheres very firmly fey means
of vessels with the substance of bones, and its external surface
is connected with cellular membrane, muscles, and ligaments.

Use. To distribute the vessels on the external and internal
smfaces of bones, to which it also gives smoothness for the
easier motion of muscles on its surface.

Diseased appearances. Inflammation, in which there is a
greater quantity of red vessels than in health, and a general
thickening. Gummi, or an elevation of the periosteum, from
ei spongy thickening.

Many have contended for the insensibility of the perios-
teum ; in a diseased state, however, it is highly sen-
sible, and often gives excruciating pain.

In some birds the periosteum is black, and green in some
fish,

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