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Show 180 MR. J. B. SUTTON ON T H E [Mar. 18, This form of the disease is most frequent among the smaller mammals, e.g. those of the genera Canis, Cynictis, Ichneumon, &c. b. Late Bickets (Rickets occurring at puberty).-At the age of puberty the disease presents certain peculiar features. In the first place it does not tend to generalize itself as in the form just considered, for it may attack the axial skeleton only, and in some cases affects the skull alone. The deformity is not so marked as in rickets of infancy. Fig. 2. A longitudinal section through the last dorsal and first lumbar vertebra of a Lion affected with " late rickets." It shows the proliferation of the tissue in the neighbourhood of the epiphysial plate, and the abnormal size of the intervertebral disk, bulging into the neural canal and compressing the spinal cord. Its chief features are as follows :-Beading at the costal junctions is fairly constant. If the epiphysial cartilages are affected, the spongioid tissue is wanting, and a small quantity of fibrous tissue developes in its place ; the line of the epiphysis is irregular. On this I place considerable importance as a sign of disease. If the epiphysial plates of the vertebrae become affected, and this they are very prone to do, the proliferation may give rise to pressure on the spinal cord, and subsequent paraplegia as shown in the drawing (fig. 2), taken from a nearly full-grown Lion affected with this form of the disease. Hypertrophy of the skull-vault is very common ; it may exceed the usual thickness five or six times, the base of the cranium remaining unaffected. The teeth are large, defective in number, and |