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Adelchi Negri 
discovery of these bodies the latter have come to be regarded as of 
prime importance in the diagnosis of rabies. Negri demonstrated 
successively the constant presence of these bodies in the nervous system 
of man, rabbits, dogs, and various other animals affected with rabies. 
From the start he regarded the bodies as parasitic Protozoa, and he 
subsequently traced out with much patient labour the supposed cycle 
of development of Neuroryctes hydroiyhohiae Calkins. He devoted 
nearly ten years of his life to the study of rabies. 
Although his chief contributions related to rabies, he also turned 
his attention to other subjects. He worked upon bacillary dysentery, 
and was the first to show that vaccine virus traverses bacterial (Berkefeld) 
filters. 
He, moreover, made important observations upon Haemoproteus, 
and especially upon Sarcocystis muris (Blanchard) Labbe. Although 
he was forestalled by Theobald Smith (1905), who successfully transmitted 
S. muris by feeding healthy mice upon the muscles of infected mice, 
he went further in that he transmitted the parasite in a similar manner 
from affected rats to healthy rats and guinea-pigs. He proved thereby 
that one species of Sarcocystis may occur in different species of hosts, an 
observation which throws grave’ doubt upon the validity of numerous 
so-called species of Sarcocystis which have been described from different 
species of animals. Doubts as to the validity of some of these species 
are, moreover, justified by Negri’s finding that S. muris differs in its 
morphology according as it occurs in the rat or guinea-pig. It should 
be mentioned, in this connection, that Negri’s views regarding the cycle 
of development of this parasite differ from those advanced by other 
authors, and they appear justified in the light of his painstaking 
experimental work. 
During the last three years of his life Negri took a very active part 
in the campaign against malaria in Lombardy concerning which he 
issued two reports. 
Negri carried on his work for years with unabated zeal and enthusiasm 
in spite of increasing infirmity, and he won the regard and admu'ation 
of all who knew him. Although the writer had not the privilege of 
knowing him personally, a correspondence extending over several years 
confirmed him in the belief that Negri was one of the most obliging of 
men, and it is with a keen sense of the loss which science has sustained 
through his premature death that this tribute is offered to his memory. 
G. H. F. N. 
