DOI Page / Citation link:
https://doi.org/10.11588/diglit.6271#0103
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m which the bony matter is deposited ; bone continues to be
separated, and the absorbents model the mass into its required
shape.
The process of ossification is extremely rapid in utero ; it
advances slowly after birth, and is not completed in the human
body till about the twentieth year.
Ossification in the fiat bones, as those of the skull, always
begins from central points, and the radiated fibres meet the
radii of other ossifying points, or edges of the adjoining bone.
In these bones the ossific matter is deposited between mem-
branes; whilst in some fiat bones, as the ossa ilia, the deposi-
tion takes place in cartilage.
In long bones, as those of the arm and leg, the clavicle,
metacarpal, and metatarsal bones, a central ring is formed in
the body of the bone, the head and extremities being carti-
lage, in the centre of which ossification afterwards begins.
The central ring of the body shoots its bony fibres towards
the head and extremities, which extend towards the body of
the bone. The head and extremities at length come so close
to the body as to be merely separated by a cartilage, which
becomes gradually thinner until the twentieth year.
Thick and round bones, as those of the tarsus, carpus, ster-
num, and patella, are at first all cartilage; ossification be-
gins in the centre of each.
At birth, the bones of the fcetus are very imperfect. The ex-
tremities and processes of almost all the long bones are con-
nected to the body of the bone by cartilage. These portions
of bone are called epiphyses. The cranium has no sutures ; its
bones are connected together by a firm and almost cartilagi-
nous membrane. On the anterior part of the cranium, be.
tween the parietal bones and the frontal, is a considerable
membranous space, called the anterior fontanel, and a similar,
m which the bony matter is deposited ; bone continues to be
separated, and the absorbents model the mass into its required
shape.
The process of ossification is extremely rapid in utero ; it
advances slowly after birth, and is not completed in the human
body till about the twentieth year.
Ossification in the fiat bones, as those of the skull, always
begins from central points, and the radiated fibres meet the
radii of other ossifying points, or edges of the adjoining bone.
In these bones the ossific matter is deposited between mem-
branes; whilst in some fiat bones, as the ossa ilia, the deposi-
tion takes place in cartilage.
In long bones, as those of the arm and leg, the clavicle,
metacarpal, and metatarsal bones, a central ring is formed in
the body of the bone, the head and extremities being carti-
lage, in the centre of which ossification afterwards begins.
The central ring of the body shoots its bony fibres towards
the head and extremities, which extend towards the body of
the bone. The head and extremities at length come so close
to the body as to be merely separated by a cartilage, which
becomes gradually thinner until the twentieth year.
Thick and round bones, as those of the tarsus, carpus, ster-
num, and patella, are at first all cartilage; ossification be-
gins in the centre of each.
At birth, the bones of the fcetus are very imperfect. The ex-
tremities and processes of almost all the long bones are con-
nected to the body of the bone by cartilage. These portions
of bone are called epiphyses. The cranium has no sutures ; its
bones are connected together by a firm and almost cartilagi-
nous membrane. On the anterior part of the cranium, be.
tween the parietal bones and the frontal, is a considerable
membranous space, called the anterior fontanel, and a similar,