566 Microscopic Organisms in Blood and their Relation to Disease, [part hi. 



rods (Fig. 37, B) ; 3, Vibriones, short, undulating filaments manifesting somewhat screw- 

 like movements (Fig. 37, C) ; 4, Bacilli, or Vibrio-bacilli — fine, short filaments, indistinctly 

 jointed, which, when they attain considerable length, are sometimes described as leptothrix 

 filaments (Fig. 37, D) ; 5, Spirilla — fine, more or less flexible, spiral filaments, which 

 manifest well-marked screw-like movements (Fig. 37, E). 



It may be mentioned, in passing, that examples of each of these forms may, 

 commonly, be detected in the muco-salivary fluid from the mouth of healthy persons. 



The question which naturally suggests itself now is : Under what condition are 

 organisms of this character found in the blood ? M. Pasteur states that the blood in 

 health is absolutely free from anything of the kind. His words are : " Le sang d'un 

 animal en pleine sant^ ne renferme jamais d'organismes microscopiques ni leurs germes." * 

 Dr. Beale, on the other hand, says, " The higher life is, I think, interpenetrated, as it 

 were, by the lowest life. Probably there is not a tissue in which these germs are not ; 



Fig. 37. — Various forms of Fission-iungi—SnJikomycetes x 600 diam. 



A. Spherical bacteria {Bncterium 2>u>ictum). 



B. Elongated bacteria {Bactermm termo). 



C. Vibriones. 



D. Bacilli. 



E. Spirilla. 



nor is the blood of man free from them." t It may appear strange that the satisfactory 

 settlement of a question, apparently so very simple, should hitherto have proved impossible 

 and that many eminent observers should have arrived at opposite conclusions regarding it. 

 It may be that to a certain extent both classes of observers are in the right, for if, as is 

 not uncommonly affirmed, very many of these extremely minute organisms constantly 

 find their way into the circulation through the lungs and pass through the walls of the 

 intestinal tract along with the food (that bacteria pass with fluids through a mem- 

 branous septum is a well-ascertained fact, as also that they will pass through porous 

 earthenware and other filtering media), it is very certain that their existence in the 

 plasma of healthy blood is of comparatively short duration. 



This point has been definitely settled as the result of observation by many patho- 



* Compter Rendug, t. Ixxxv, p. 108 ; 16th July, 1877. 

 f DiMafr Germs, 1870, p. 64. 



