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instance, drawn from an external source ; but, differing from 

 them in the fact that " the poison only originates outside 

 the body when an affected body has furnished the germs. " 

 This division includes typhoid fever, cholera, dysentery, 

 yellow fever, the plague, dengue, miliary fever, influenza, 

 hay fever, epidemic cerebro-spinal meningitis, and, perhaps 

 whooping cough; and the mode of extension of these diseases 

 is so far understood as to enable us to state with certainty 

 that they can neither be reckoned among the contagious nor 

 among the miasmatic diseases according to the following 

 definition : Contagium has been defined as a specific excitant 

 of disease, which originates in the organism suffering from 

 the specific disease ; while miasm, on the other hand, is the 

 term used to denominate a specific excitant of disease, 

 which propagates itself outside of, and disconnected from, 

 a previously diseased organism. Contagium can be con- 

 veyed by contact from a diseased person to a sound one, 

 produce the disease in him, and then again reproduce itself. 

 Miasm originates from without ; taken up into the body, it 

 can call a specific disease into action, but it cannot spread 

 the disease any further by conveying it from a diseased to- 

 a sound person. 1 Seeing then that the diseases just 

 enumerated are neither contagious nor miasmatic according 

 to the above definition, while possessing some of the char- 

 acteristics of both, it seems but right to include them in a 

 third group, to which the name miasmatic-contagious has 

 been given, which, moreover, they have held for a consider- 

 able period, though usually in another sense. As in the 

 two previous divisions, and for similar reasons, we can trace 

 no potential causative agency to the influence of heredity in 

 this one, apart from the fact that the protophytic fungi, some 

 1 Liebermeister. 



