THE CHOLERA SPIRILLUM. 377 



regulatory mechanisms are specially involved. In some, 

 though rare, cases known as cholera sicca, general collapse 

 occurs with remarkable suddenness, and is rapidly followed 

 by a fatal result, whilst there is little or no evacuation from 

 the bowel, though post mortem the intestine is distended 

 with fluid contents. As the characteristic organisms in 

 cholera are found only in the intestine, the general dis- 

 turbances are to be regarded as the result of toxic sub- 

 stances absorbed from the bowel. It is also to be noted 

 that cholera is a disease of which the onset and course are 

 much more rapid 

 than is the case in rO * 



most infective ^ fe^ ^ 



diseases, such as V O- '**y .M * "^ 



typhoid and diph- C rN 3 ^V'v*' '/ - 



theria ; and that | ^7 ^ ^ ^ >C 

 recovery also, when t-C C C 



it takes place, does ->*.. W. " ' 

 so more quickl The ' 



two factors to be co- IK 

 related to these facts 



~+ AT 



- ''V^ 

 V s s %JN 



are (a) a rapid multi- 



plication of organisms, 



(^) the production of "* ^ ^ u y> 



rapidly acting toxines. 



The Cholera Spiril- FlG " 92. -Cholera spirilla, from a culture 



* on agar of twenty-four hours' growth. 



lum. Microscopical Stained with weak carbol-fuchsin. x 1000. 



Characters. The 



cholera spirilla as found in the intestines in cholera are small 

 organisms measuring about i . 5 to 2 p in length, and rather less 

 than .5 in thickness. They are distinctly curved in one 

 direction, hence the appearance of a comma (Fig. 92); most 

 occur singly, but some are attached in pairs and curved in 

 opposite directions, so that an S-shape results. Longer 

 forms are rarely seen in the intestine, but in cultures in 

 fluids, as is especially well seen in hanging-drop preparations, 

 they may grow into longer spiral filaments, showing a large 

 number of turns. If film preparations be made from the 



