72 THE GERMINATION OF THE ENDOSPORE. 



in B. subtilis; consequently, if the former were by Buchner's 

 treatment not only rendered harmless, but also actually converted 

 into B. subtilis^ then the course of germination must also have 

 become correspondingly changed. Starting with this assumption, 

 PRAZMOWSKI (III.) subjected a weakened anthrax bacillus (pre- 

 sumably transformed into B. subtilis) to examination with regard 

 to the nature of the formation and germination of its spores. He 

 found that both operations pursued exactly the same course as in 

 the virulent (unweakened) anthrax bacillus, thereby disproving the 



assumption of the identity of the 

 two species. 



The first observation of the pro- 

 duction of developing reproductive 

 cells within the bacterial cell was 

 made by PERTY (I.) in 1852. who 

 designated the rods he found to 

 possess this property Sporonema 

 gracile (Fig. 28). His communica- 

 tion, however, met with no recog- 

 nition and fell into oblivion. About 

 fifteen years later PASTEUR (VI.), 

 unaware of Perty's observation, 

 re-discovered the same fact in the 

 course of his researches on the 

 causes of lethargy in silkworms 

 (gattine). The fission fungi which 

 b-g. Sporonema gracile ; 6. with one he found in large number in the 



terminal spore ; c. with two spores ; i- ^ , ? ,- ,-, -j- i 



in d the spore has escaped from the alimentary canal ot tne diseased 

 mother-ceil; e-g shows the gradual (lethargic) worms, and which he 



development of the spore until v . , i 



ripe, in a is shown the (formerly) experimentally ascertained to be 



so-called Metallacter, a chain of t Up , f *!<. crpnprallv fatal 

 short threads which when viewed tne cause tnis generally latal 

 under a low power is apt to be epidemic, frequently exhibited in- 

 mistaken for a long rod, hence its .* in-jLl BTin lAfliipftfl thp for 

 name. ueiiidi iuoiioub enciosuieo, me 101 



mation and function of which he 



explained to be reproduction by endogenous germs ("reproduc- 

 tion par noifdux interieurs "), without, however, observing them 

 more closely in order to ascertain the accuracy of this hypothesis. 

 Only one proof was needed to set this beyond doubt, namely, 

 the demonstration that these forms have the faculty of germinat- 

 ing and of developing into new individuals. FERD. COHEN (VII.) 

 first succeeded in doing this, in 1876, with a bacillus isolated by 

 him from an infusion of hay. This fact definitely proved that the 

 bacteria belong to the vegetable kingdom, since spore formation 

 exclusively characterises the sub-kingdom Thallopln/ta, and is un- 

 known in animals. A more accurate acconntof this important process 

 was given two years later by OSKAR BREFELD (I.) for Bacillus sub- 

 tilis ; two years subsequently by A. PRAZMOWSKI (I.) for Clostridium 

 butyricum; in 1882 by HANS BUCHNER (II.) for B. anthracis; 

 then by DE BARY (I.) for his B. megatherium, and by others. 



FIG. 28. 



Spore formation according to Perty. 



