^ iii.j Endosporous Bacteria. 17 



The details of these processes disclose sundry variations of 

 diagnostic value, especially in connection with the shape. In 

 Bacillus Megateriura, B. Anthracis, B. subtilis, for example, the 

 sporogenous cell does not differ in shape from the vegetative 

 cell, but in the two latter the mature spore is much shorter ; in 

 B. Anthracis it is slightly narrower, in B. subtilis often rather 

 broader than the mother-cell, in B. Megaterium it is a little 

 shorter but much narrower than the comparatively short 

 mother-cell (cf. Figs, i and 2). 



In other species the spores are much smaller in every 

 direction than the mother- cell, and the latter is distinguished 

 from the cylindrical vegetative cell before or during the form- 

 ation of the spore by swelling into a permanent fusiform or 

 ovoid shape, either over the entire area of the cell or at the spot 

 where the spore lies, and which is then usually at one ex- 

 tremity of the cell. In the latter case, and also when cells that 

 are still cylindrical are attached on one side to a mother-cell 

 which has swollen up all over, the forms are produced which 

 were once known as capitate Bacteria, cylindrical Bacteria 

 with a capitate sporogenous swelling at the extremity. Ex- 

 amples of this kind are Bacillus Amylobacter (Fig. 13), B. 

 Ulna, and some others. 



In Bacillus Amylobacter and Spirillum amyliferum, v. Tiegh., 

 the appearance of the spore is preceded by the formation of 

 granulose described above, and the spot where the spore 



p.m., e about one hour later,yone hour later than e. The spores in /"were 

 mature by evening ; no others were formed ; the one apparently commenced 

 in the third upper cell of d and e disappeared; the cells in _/" which did 

 not contain spores were dead by 9 p.m. r a four-celled rod with ripe 

 spores, g^ five-celled rod with three ripe spores placed in a nutrient 

 solution after drying for several days, at 12.30 p.m.; ^^ the same speci- 

 men about 1.30 p.m.; g^ about 4 p.m. hi two dried spores with the mem- 

 brane of the mother-cell placed in a nutrient solution, about 11.45 ^•™- \ 

 h^ the same specimen about 12.30 p.m. i, k, I later stages of germination 

 explained in the text on p. 2 1 . m rod dividing transversely, grown from a 

 spore placed eight hours before in a nutrient solution, a magnified 250 

 times ; the other figures 600 times. 



