9 6 



MORPHOLOGY AND CULTURE OF MICROORGANISMS 



These results have been confirmed by our studies of a large number 

 of endospore bacilli (B. megatherium, radicosus, mycoides, aster ospor us, 

 alvei). Upon examination at the very outset of their development, 

 these bacteria present a homogeneous appearance and are uniformly 



1 



. / 



FIG. 74. Bacillus sporonema. i, Cell about to sporulate. 2, This cell grows 

 narrow at the center, as if it were going to be divided (Schaudinn regards this pinch- 

 ing together which afterward disappears (5), as the vestige of an ancestral sexuality 

 like that of B. biitschlii). 3-5, Formation of the beginning of the spore. (After 

 Schaiidinn.) 



stained with no great differentiation, explicable by the density of the 

 cytoplasm or by a special condition of the membrane. At this stage 

 the cells are in the process of active divisions, after which the transverse 

 septa are formed as follows: On the side walls of the bacillus appear 

 two small granules which take some stains (Fig. 75, i). These soon 



FIG. 75. i-io, Bacillus radicosus. i, Beginning of development. 2-3, Cells 

 at the end of eight hours; 4-6, sporulation. 9-10, Cells in which the chromatic 

 grains are located in the middle in a mass slightly resembling a nucleus. 11-12, 

 Spirillum volutans. 



disintegrate at the center of the cell to form a thin band marking out 

 the two daughter cells and forming the beginning of the transverse 

 septum. This strongly resembles a nucleus and has apparently been 

 considered as such by a number of authors (Rayman and Krius, Mencl). 

 Toward the eighth hour of development, the cells show clearly their 



