154 
HISTOLOGY OF ANIMALS. 
in the foetus, it is indicated by the dotted line in 
Fig. 117, c ; the vessels of the cartilage, which in this 
instance are very numerous, being derived from those 
of the articulation, and not from those of the shaft. 
The non-vascular character of healthy articular carti- 
lage, is maintained from the period of youth to old age ; 
but, if disease occur, vessels may soon be found in it. 
In a specimen from a diseased joint, which after removal 
was carefully injected, numerous vessels may be observed 
passing through the cartilage ; they are derived from 
the vessels of the shaft, as the articular lamella being 
involved in the disease, permits the vessels to pass 
through it ; they proceed in straight lines through the 
cartilage to the free articular surface upon which they 
form a network, and anastomose with others probably 
derived from the synovial membrane. The subject 
from whom this specimen of cartilage was obtained was 
fifty years of age, and the disease had existed for 
nearly twelve months. A preparation which belonged 
to the late Mr. Liston, and 
which he was in the habit of 
exhibiting in his Lectures, con- 
sists of the head of the tibia, 
with diseased cartilage at- 
tached. Not only can vessels 
be seen by the naked eye, pas- 
sing from the bony shaft into 
the cartilage, in the form of 
loops, as in Fig. 119, but a 
FIG. 119 . 
Section of diseased articular 
cartilage largely supplied with 
vessels. 
