136 NEW YORK ZOOLOGICAL SOCIETY. 



cine, and in .general scicntihc ])r( uluclions, that it is indeed a most 

 difficult task fi»r one to assure liimself that any subject has here- 

 tofore remained undcsoribcd. 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 fullv 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 imder 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. XXXVII, s. 433) 

 mentions the condition, but does not discuss it at any length as 

 a])plied 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-P.ook 

 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 "stififness" which is charac- 

 teristic of the early stages of the malady. Sanyal. however, con- 

 sidered it as ])riniaril\- a ])aralysis. 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. Undoul)tt dly osteo- 

 malacia of the Primates, as in man, has long Ixhh confused with 

 rachitis, which it very closely similates, particularl\ in the slowly 

 progressive cases where extensive deformities lia\e taken place. 



The lesions in the bones are verv similar in Ixith cases, and 

 even clinically thev closely resemble eneli otlur. 1"he essential 

 point of dififcrencc exists in that in rachitis we are dealing with 

 a congenital state in which the bones were never normallv calci- 

 fied, while in osteomalacia the disease is an :ic(|uir((l <inc in wliicli 

 the once nrirmally calcified bones become dec.ilciticil. 



The dilTerentiation, however, is just as clciir and tlir same as 



