FISSION FUNGI AS CAUSAL AGENTS OF DISEASE. 641 



disturbance of the tissue change and of the arrangements 

 which regulate the functions of the body, and this dis- 

 turbance goes on till severe general morbid symptoms 

 occur, which usually lead to death. Some of the micro- Embolism, 

 organisms which belong to this class may very readily 

 lead to blocking of the smaller blood-vessels, either by 

 their accumulation in large numbers, or by the heap- 

 ing up of materials which have arisen from the break- 

 ing up of the plasma cells ; in such cases there very 

 readily occurs, in parts, necrosis of the surrounding 

 tissue, and subsequent development of the bacteria in 

 this tissue, which still further degenerates under the 

 direct action of the organisms. At times the most active 

 multiplication of the bacteria in the capillary system 

 only occurs in one or some organs which are particularly 

 predisposed, and thus the emboli often show a predilec- 

 tion for certain organs. Thus it happens that the local 

 symptoms are often the most striking, and that the type 

 of the disease varies markedly, according as in the one 

 case the general phenomena, in the other, these or those 

 local symptoms are prominent. 



The power possessed by a limited number of bacteria Biological 

 of leading a parasitic existence in the body of warm- of tSe patifo- 

 blooded animals raises the question to what biological genie bacteria, 

 peculiarities of these bacteria this power is due ; what 

 differences exist between their properties and those of 

 the saprophytic bacteria ; what are the protective arrange- 

 ments of the living body which render the multiplica- 

 tion and development of the latter impossible, but which, 

 on the other hand, are powerless against these patho- 

 genic bacteria ? 



The attempt was formerly made to explain this rela- Eesistance 

 tion by the aid of some one active factor in the living J^^^enta of 

 organism. Thus, it has been pointed out that it is the fluids of 



-ui xi A \ i .the body? 



possible that some bacteria can only grow in a quiescent 



medium and not in the fluids of the body which are in 

 active movement, and it has been supposed that 



41 



