FIBRO-CARTILAGE. 
177 
nearly equal distances from each other, and occa- 
sionally, portions of the tubes may be seen in the 
apertures. Dr. Reid described very accurately the struc- 
ture of the vertebrae, and the arrangement of these 
thick-walled cells, but he appears to have overlooked 
the tubes passing through them, as no mention is made 
of their presence in his paper on this subject, published 
in the “Annals of Natural History” for 1849. They 
may not be present in every vertebra, but they are so in 
all the specimens in my possession, which were trans- 
mitted to me from Dr. Reid himself, through the hands 
of Dr. Macdonald. 
FXBRO - CARTILAGE. 
Before concluding the subject of cartilage, there is 
another tissue which, from being composed of two 
simple elements, fibrous tissue and cartilage, has been 
placed by Messrs. Todd and Bowman, as the last of 
the tissues in their table, namely, fibro-cartilage ; but, as 
this is so intimately connected with some of the forms 
of articular cartilage and enchondroma, I think it best 
to consider it in this place. 
Fibro-cartilage exists principally in articulations, 
occurring in the form of discs between the vertebrae 
in the human subject ; these are highly elastic, and 
serve to diminish the shocks to which this portion of 
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