Under these circumstances the
humerus and femur appear to be the bones most likely to break; there is
an associate deformity of the head, known as "craniotabes," together
with pigeon-breast and various spinal curvature. The accompanying
illustration is from a drawing of a skeleton in the Warren Museum in
Boston. The subject was an Indian, twenty-one years of age, one of the
Six Nations. His mode of locomotion was by a large wooden bowl, in
which he sat and moved forward by advancing first one side of the bowl
and then the other, by means of his hands. The nodules or "adventitious
joints" were the result of imperfect ossification, or, in other words,
of motion before ossification was completed.

Analogous to rachitis is achondroplasia, or the so called fetal
rickets--a disease in which deformity results from an arrest, absence,
or perversion of the normal process of enchondral ossification. It is
decidedly an intrauterine affection, and the great majority of fetuses
die in utero. Thomson reports three living cases of achondroplasia. The
first was a child five months of age, of pale complexion, bright and
intelligent, its head measuring 23 inches in length. There was a narrow
thorax showing the distinct beads of rickets; the upper and lower limbs
were very short, but improved under antirachitic treatment. The child
died of pneumonia. The other two cases were in adults, one thirty-nine
and the other thirty-six. The men were the same height, 49 inches, and
resembled each other in all particulars. They both enjoyed good
health, and, though somewhat dwarfed, were of considerable
intelligence. Neither had married. Both the upper and; lower limbs
showed exaggerations of the normal curves; the hands and feet were
broad and short; the gait of both of these little men was waddling, the
hunk swaying when they attempted to make any rapid progress.

Osteitis deformans is a hyperplasia of bone described by Paget in 1856.
Paget's patient was a gentleman of forty-six who had always enjoyed
good health; without assignable cause he began to be subject to aching
pains in the thighs and legs. The bones of the left leg began to
increase in size, and a year or two later the left femur; also enlarged
considerably. During a period of twenty years these changes were
followed by a growth of other bones. The spine became firm and; rigid,
the head increased 5 1/4 inches in circumference. The bones of the face
were not affected. When standing, th