102 MICRO-ORGANISMS AND DISEASE [chap, 



were other than single elements. These elements he has 

 seen to give origin almost simultaneously to as many as 

 four short slightly rod-shaped elements ; and these same 

 elements were, on continued observation, seen to elongate 

 and the terminals within several minutes seen to have in- 

 creased almost to twice their length, then each of them 

 again to have divided, one into three, the other into two 

 distinct rods. 



Observations were carried out on a filamentous bacillus 

 isolated from sewage liquefying gelatine as a clear fluid ; 

 it was non-motile, rapidly growing into threads, and in the 

 filaments copious spore formation took place ; this bacillus 

 resembled morphologically the bacillus anthracis, but it 

 grows on the surface of gelatine more as a continuous 

 membrane of threads arranged parallel and coming off at 

 right angle from a central stalk ; it grows much more 

 rapidly than the bacillus anthracis. 



Now, directly observing under the microscope the growth 

 and multiplication of this bacillus in solidified gelatine, 

 threads of bacilli are seen shooting out with considerable 

 rapidity from a short cylindrical bacillus measuring o'^/jl, 

 to ifji, a thread more or less wavy is formed in the course of 

 two hours and a half, which extends across the whole field 

 of the microscope under a magnifying power of 500. On 

 such a growing thread the simultaneous division after elonga- 

 tion of cylindrical elements into three and four rods is also 

 distinctly and repeatedly noticed. 



Also on the rods of the bacillus of diphtheria the same 

 simultaneous fission of elementary cylindrical cells into two, 

 three, and four elements was noticed. We conclude then 

 that in the division of bacilli the elements increase in length 

 and then by transverse fission divide into two, three, or four 

 elements, and according to the length of the cell before 



