OSTEOMALACIA OF PRIMATES IN CAPTIVITY. 
A CLINICAL AND PATHOLOGICAL STUDY OF “CAGE PARALYSIS.” 
FROM THE MEDICAL DEPARTMENT OF THE NEW YORK ZOOLOGICAL PARK. 
By HARLOW BROOKS and W. REID BLAIR. 
es AGE paralysis” or “cripples” is a condition of such fre- 
quent occurrence, particularly among the primates, that 
it forms one of the most serious obstacles to the maintenance of 
large and complete collections of wild animals in captivity. 
Judging from the frequent inquiries which have been addressed 
to us regarding this condition, and from statistical reports from 
other collections, we have been more fortunate in the small num- 
ber of fatalities from this complaint than most parks of similar 
size, and yet the death-rate from this disease has headed the list 
among our primates since tuberculosis has practically been eradi- 
cated from the collection. For this reason, and as a matter of 
sure scientific interest, our attention has been particularly directed 
toward “cage paralysis” for the past two years. 
In the Report of the New York Zoological Society for 1903, 
one of us (Brooks) presented a small series of cases studied from 
the standpoint that the disease was primarily one of the central 
nervous system. As a result of this preliminary study it was 
concluded that the condition, as recognized by animal men, was 
not a true disease entity, but that it really represented a very 
wide group of spinal and cerebral disorders, probably covering as 
extensive a field as the similar groups of human cerebro-spinal 
diseases. 
During the past year we have carefully observed all instances 
of the malady as it appeared in our collection and, as a result, 
one of us (Blair) has noted a series of lesions which, after con- 
siderable study, we believe to be primary and essential to the dis- 
ease in any form, and which causes us to unhesitatingly class it 
as osteomalacia. 
The studies appearing on diseases of wild animals are so few 
and so widely distributed throughout the enormous literature 
of zoology, veterinary medicine, human and experimental medi- 
