STAINING OF FLAGELLA. 141 



also coloured. A varying number of fine undalating 

 curved threads are also seen stretching out in an irre- 

 gular manner from the bodies of the bacilli ; these are 

 much less intensely stained, and in the most successful 

 cases only appear a dark pink. Sometimes they ap- 

 pear to be attached to only one point of the bacillus, 

 sometimes they are distributed over the whole body, 

 sometimes they are very long, sometimes short, some- 

 times more on one side, sometimes all on one pole; 

 in short, there may be great variations in the way the 

 flagella grow even in one species. On the other 

 hand, however, there are usually quite distinct features 

 which are constant to the various species, and which 

 are sometimes of the greatest use in distinguishing 

 them one from another. We find, if we examine 

 especially for it, that in a given species the greater 

 number o£ the flagella are distributed over the whole 

 body, or that they are in a bunch at one pole or at 

 both poles, or that only one or two (rarely three) occur 

 at each pole. 



The following bacilli amongst others have numerous 

 flagella distributed over the whole body : The typhoid 

 bacillus, the bacillus of blue milk {bacillus cycmogenus) , 

 the potato bacillus {bacillus mesentericus vulgatus), 

 the bacillus of malignant oedema, the bacillus of 

 Rauschbrand, the bacillus suhtilis, the ferret plague 

 bacillus, the bacillus proteus, etc. 



The following have only one or two flagella "at the 



