CHAPTER VI. 



THE GERMINATION OF THE ENDOSPORE. 



56. First Type. 



WHEN the spore is exposed to favourable conditions as regards 

 nutrition, it abandons its dormant state and begins to germinate 

 by commencing to absorb liquid from the surrounding medium. 

 It then becomes distended, its high refractive power gradually 

 diminishing in the same proportion. Further development can 

 then proceed in three ways. 



The first type of spore germination was accurately observed by 



H. BUCHNER (III.) in Bacillus anthracis, the producer of anthrax, 



and afterwards discovered in other kinds; 



ffo as, for instance, by PRAZMOWSKI (II.) in a 



| U fission fungus named by him " mistbakterie " 



4.2.JP (dung-bacterium), and in a second species 



isolated from fermenting urine. The prog- 



FIO. 21. ,,! 



Bacillus anthracis.' ress of germination in this type is very 

 Germination of spores. Dimple (Fig. 2 1 ). The spore, gradually acquir- 

 * the ripe spore before in *" e norina l dimensions and functions 

 germination begins ; of the vegetative form, soon divides and re- 

 stages' of 'glimSatSInl produces by fission. According to several 

 3 ^ the /^l ly Developed observations made by Brefeld, the external 



rod. (Ajter JJe Hary.) f . " . . 7 



Magn. about 600-700. layer of the spore-membrane (" exospormm ") 

 separates during this germination process 



and swells up. This harmonises well with the remark made in 

 a previous paragraph, that the spore-capsule probably consists of 

 two layers, distinguished as exosporium and endosporium. 



57. Second Type of Spore Germination. 



Microscopically the initial stage of the process is identical 

 with that described in the foregoing paragraph ; the refraction 

 of the spore diminishes and an increase in size occurs. Then, 

 however, the contents of the spore are elaborated into a new 

 rod which is surrounded by a thin membrane, and which, by its 

 further growth, bursts the spore capsule. 



This rupture is effected at the point of least resistance, the 

 position of which and consequently the mode of escape of the 

 germ varies in different species. 



