PART III.] 



Production of Germinating Spores. 



573 



contained plenty, whereas in guinea-pigs the number of bacilli in the blood was 

 often so great as to equal, if not exceed, that of the red blood-corpuscles. 



On adding a little of the spleen affected with bacilli to perfectly fresh aqueous 

 humor and subjecting the preparation to a temperature of 35-37° C. for from 15 

 to 20 hours, the bacilli became elongated to from twice to eight times their 

 original length, and gradually still further increased, till more than a hundred times 

 this length (Fig. 40). Some of the filaments were now finely granular, and, here and 

 there, dotted with strongly refractive molecules, which are believed to be the desired 

 " resting-spores." Very soon nothing remained visible but these " spores," as the 

 filament appeared to undergo solution, but the persistence of the arrangement of the 

 former in rows is sufficiently marked to identify them. They will remain unaltered 

 in this state for several weeks. 



Fig. 39.— 7iac-tWv/.y anthvuc'm from the biood of 

 a guinea-pig : Translucent bacillus-rods, 

 undergoing segmentation. Blood-corpuscles 

 are scattered throughout the field. (After 

 Koch.) X 650 diam. 



i^'ig. i'd.- Bucilltts Anthracis from the spleen of 

 a mouse after a 3-hour '• cultivation " in a 

 drop of aqueous humor. (After Koch.) 

 X 650 diam. 



It will be remarked that the interpretation placed on the character of these 

 refringent bodies clashes with what is so strongly maintained by Nageli, who, as 

 mentioned already, declares emphatically that the group of lower organisms to which 

 these belong multiply solely by fission. It is, therefore, of greater importance to 

 note precisely what the facts adduced are, to prove that in this special instance ger- 

 minating spores are produced. 



Dr. Koch states that the fact of his being able to induce splenic fever, together 

 with a plentiful crop of bacilli in the blood, with fluid in which not a trace of a 

 bacillus filament is any longer to be found — the minute refractive corpuscles alone 

 remaining, is proof sufficient to show that the latter are in reality spo^^es, and not 

 products of disintegration merely. Cultivation-experiments were, however, also under- 

 taken, and it was found that in the course of 3 to 4 hours the development of these 



