76 DISEASES DUE TO 



inactive and dormant as long as the cell remained 

 vigorous and healthy, but sooner or later, if not from 

 disease, from old age, changes must occur by which 

 a state of things results which is favourable to the 

 germs whose turn invariably comes at last. These 

 grow and multiply and live upon the dead germinal 

 matter and the" altered and softened formed mate- 

 rial of the cells. We must, in the absence of positive 

 demonstration, hesitate to accept the doctrine that 

 the lowest organisms may result from degradation of 

 the living matter, which at one time formed a part of 

 a higher being. But we may refuse to accept the state- 

 ments which have been made as to the direct conver- 

 sion of the fibrillae or discs of striped muscle into 

 bacteria, because such assertions are contradicted by 

 well-known facts. From the red blood corpuscles may 

 be made bodies which might be mistaken for bacteria ; 

 nay, if the most practised observer were to examine 

 one of these bodies only by itself, he might easily be 

 deceived. The little beaded filaments exhibit move- 

 ments which, though differing from the movements of 

 the bacteria, would certainly be mistaken for them 

 by an unpractised observer. But it ought not to be 

 necessary to state, that in microscopical research mere 

 resemblance in external form and general characters 

 should not be accepted as proof of identity of nature 

 any more than in ordinary observation. 



Of Diseases known to be due to Vegetable Organisms. 

 The diseases of man and the higher animals, known 



