136 NEW YORK ZOOLOGICAL, SOCIEDY. 
cine, and in general scientific productions, that it is indeed a most 
difficult task for one to assure himself that any subject has here- 
tofore remained undescribed. It is perhaps for this reason that 
we have found but very few references to osteomalacia occurring 
in wild animals and, indeed, until some time after we ourselves 
had fully decided as to the nature of the disease, we were unaware 
that the condition had been previously noted. The recognition 
of “cage paralysis,’ familiar to all animal men under that name, 
as osteomalacia, we believe to be now stated for the first time. 
Osteomalacia occurring in domestic animals has long been 
recognized and has been fully studied, particularly by the work 
of Roloff, Ribbert, Pillvax, Rool, Haubner and Anaker. 
Of these writers but one, in so far as we have been able to 
find, has described the disease as occurring also in wild animals. 
Roloff as early as 1867 (Virchows Archiv. Bd. XX XVII, s. 433) 
mentions the condition, but does not discuss it at any length as 
applied to these animals. 
It is not infrequently mentioned in various Zoological Society 
reports, but, so far as we have been able to learn, in none of them 
has the true nature of the condition been ascertained. Thus 
among the earlier records we find Ram Brahma Sanyal, Super- 
intendent of the Zoological Garden of Calcutta (“Hand-Book 
of the Management of Animals in Captivity in Lower Bengal,” 
1892), mentions the prevalence of the “cripples” among Diana 
and other monkeys. He attributes the disease to damp and cold, 
stating that no treatment relieved the “stiffness” which is charac- 
teristic of the early stages of the malady. Sanyal, however, con- 
sidered it as primarily a paralysis, and did not note the osseous 
lesions. ; 
Scattered throughout the comparative studies of the central 
nervous system are also occasional references to the disease, 
treated in all instances as a primary nervous disorder, an opinion 
with which most animal men coincide. Undoubtedly osteo- 
malacia of the Primates, as in man, has long been confused with 
rachitis, which it very closely similates, particularly in the slowly 
progressive cases where extensive deformities have taken place. 
The lesions in the bones are very similar in both cases, and 
even clinically they closely resemble each other. The essential 
point of difference exists in that in rachitis we are dealing with 
a congenital state in which the bones were never normally calci- 
fied, while in osteomalacia the disease is an acquired one in which 
the once normally calcified bones become decalcified. 
The differentiation, however, is just as clear and the same as 
