On a Septic Microbe, dtc. By G. F. Dowdeswell. Ill 



cultivating fluid ; it is, too, generally less active, whilst it differs 

 from the B. anthracis by the segments, of which the longer rods 

 and filaments are composed, being more rounded at the ends — less 

 rectangular — than the almost cubical cells which compose the latter ; 

 it is, too, a little larger in width than either of the two other 

 microbes; though somewhat variable in the same medium, it 

 averages fully 1 micromiUimetre (O'OOl mm.) in breadth. It fre- 

 quently forms spores at one or both ends of the short rods in an 

 early stage of development ; the cells themselves develop to long 

 sinuous leptothrix filaments, the segmentation of which is obscure, 

 unless demonstrated by special reagents. It forms, as already men- 

 tioned, no zoogloea nor pellicle on the surface of the nutrient fluid, 

 and this character again distinguishes it at once from the hay bacillus ; 

 it grows difi'usely through the liquid, rendering it uniformly turbid, 

 not forming the clouds or flecks which characterize the anthrax 

 bacillus. It forms numerous spores, as may be observed in the 

 preparation under the IMicroscope. These at maturity are set free, 

 the plasma of the segments which contain them degenerating and 

 disappearing, having been used up in the reproductive process — 

 sporulation — the other segments remaining unchanged for a time, 

 till ultimately their life cycle ends in tlie same manner. This is 

 the significance of the numerous shadowy forms apparent in 

 preparations of this organism ; the wall of the cell alone remains, 

 the Hving plasma, or "protoplasm," has died and disappeared. 

 This form of degeneration in the cell was first, I believe, figured 

 and described by Dr. Klein,* in the case of B. anthracis, the 

 appearances it ofiers, which are conspicuous in the preparation 

 here shown, having sometimes been misunderstood by previous 

 observers. 



The spores when set free appear to germinate in the same 

 nutrient medium in which they were developed, as is not the case 

 with some other species ; they develop regularly in the direction of 

 their longer axis, never, as far as I have observed in innumerable 

 instances, in the excentric manner described by Brefeld f in the 

 case of B. suhtilis, and copied by so many subsequent observers 

 from him, in that case also, I may mention, quite contrary to my 

 own observations.^ 



There is a peculiarity in the spores of this organism at once 

 apparent in the preparation under the Microscope ; it is, that they 



* Rrp. Med. Oif. Loc. Govt. Bd., 1S83, and Quart. Journ. Micr. Sci., 1883. 



t But. Unt<.r8u<;h. liber Seliiinmelpiize (Leipzig, 1872) p. 4(j, &c. 



X As, however, there are at least three or four distinct Bpecics of Imy bacilli, 

 all (jf wliich are more or lea.s rcHihtent to heat, and it is dillicult accurately to 

 diagnoHe Cohn'a Bpefiiea of B. suhtilis, it is jiosHible that the Hporea of Honio one of 

 theue Hpcciea may germinate in the excentric manner descriijcd, though this haa not 

 been the caws with any of those that I have hitherto obtained, in very numerous 

 experiments, by the usual metho<l8 of Ixjiling, &c. 



