482 MICRO-ORGANISMS AND DISEASE [chap. 



whole organ is now called a perithecium. Finally the asco- 

 gonium by rapid division gives origin to a number of oval 

 septate tubes, inside of which by endogenous formation 

 numerous spores make their appearance. 



Grohe ^ was the first to show that the introduction of the 

 spores of some species of aspergillus into the vascular 

 system of rabbits sometimes produces death, with symptoms 

 of metastasis into the various organs due to localised foci, 

 where these spores grow into mycelial filaments. Lichtheim ^ 

 showed that such mycoses in rabbits cannot be produced by 

 the spores of Aspergillus glaums, but easily by those of 

 Aspergillus Jlavescetis and fuf?iigatus, less in degree by 

 Aspergillus niger. Grawitz ^ studied this process more 

 minutely, and found that, no matter whether the spores 

 are injected into the vascular system or into the peritoneal 

 cavity, there are established in the kidneys, liver, intestines, 

 lungs, muscles, and occasionally in the spleen, marrowbones, 

 lymphatic glands, nervous system, and skin, minute meta- 

 static foci, due to the growth of the spores into mycelial 

 filaments with imperfect organs of fructification, but no 

 spore-formation. Grawitz thought that the spores of ordi- 

 nary moulds (penicillium and aspergillus) are capable of 

 assuming these pathogenic properties if cultivated at higher 

 temperatures (39° to 40° C), and in alkaline media. These 

 fungi, as is well known, grow well at ordinary temperatures 

 and in acid media, and are then innocuous when introduced 

 into the animal body ; but by gradual acclimatisation they 

 can also be made to grow at higher temperatures and in 

 alkaline media, when they assume pathogenic properties, 

 becoming capable of resisting the action of living tissues 

 and of growing in them. This view has been proved to be 



1 Bcrl. klin. Woch. 1871. ^ Ibid. 9 and 10, 1882. 



^ Virchow's Archiv, vol. Ixxxi. p. 355. 



