ZOOLOGICAL DISTRIBUTION OF DISEASE, 251 
villages, unmolested and cherished by man, the traces of 
casualties among them are so rarely seen, that the simple 
Hindoo believes that they bury their dead by night,” 
As far as my own investigations have extended I find, 
excluding the affections known collectively as the acute 
exanthemata (scarlet-fever, measles, small-pox, and the 
like), that most diseases known in the human species 
occur in mammals. A few affections rare in man are 
frequent in mammals ; a limited number of diseases are 
peculiar to mankind, whilst others occur only in the 
lower animals. The inquiry is of some importance, for 
it serves to show that certain diseases. give rise to 
changes so very different in animals of one class to 
those of another class as to be described under a 
different name, whilst two distinct affections may pro- 
duce in animals belonging to different classes lesions of 
such close naked-eye resemblance that they are fre- 
quently confounded with each other. Such conditions 
raise the all-important question, “ How far is it probable 
that many of the acute contagious fevers which affect 
the human species occur in other animals, but producing 
different symptoms receive another name?” This is 
illustrated in a remarkable manner by tuberculosis, a 
disease of world-wide distribution. Writing concerning 
that common manifestation of this disease, pulmonary 
consumption, Hirsch, in his admirable Geographical and 
Historical Pathology, states that it has held at all times 
and among all civilized peoples a foremost place among 
the national diseases, and that it extends over every 
part of the habitable globe, and may be designated 
ubiquitous in the strictest meaning of the term. 
