The osseous and cartilaginous systems are confounded in the embryo; as
the first is developed, the second contracts; the latter very evidently
has gelatine for its principal base; I shall not return to the proofs
that have demonstrated it in the osseous system.
I have shown, in speaking of that system, how the cellular and vascular
parenchyma, existing at first alone and constituting the mucous state,
is penetrated afterwards with this base, which forms the cartilage. The
primitive mode of the formation of these organs is then already known.
Let us see how its development continues.