363 TEXT-BOOK OF BACTERIOLOGY. 



out the coarser particles) and injecting it into the jugular or, easier 

 still, the vein of the ear of a rabbit, its death will ensue after 

 from twenty-four to seventy-two hours. 



On post-mortem examination small and whitish nodules will be 

 found spread over all the organs, especially the kidneys and liver, 

 proving, on microscopical examination, to be densely felted mycelial 

 layers of the respective species of mould. The vessels of larger 

 calibre are, here and there, distorted by the confused network of the 

 vigorously grown filaments which, however, never develop fructify- 

 ing organs, hyphae or conidia. This will be best seen by staining 

 the sections with LofiQer's blue or Ziehl's carbol-fuchsin. Proper 

 media, especially bread-paste, will easily reproduce, at breeding 

 temperature, luxuriant growths of fungi from the organs. 



These facts led to a closer observation of more or less extensive 

 mycoses in man under natural conditions. They had been caused 

 by pathogenic kinds of aspergillus and mucor. The external audi- 

 tory canal, the nasal cavities and cornea, also the internal organs, 

 intestines, lungs and brain, were seen covered with mould fila- 

 ments whose germs had found entrance in some way. 



Among the vegetable organisms standing mid-way between the 

 mould and yeast fungi, some are distinguished by pathogenic or, 

 rather, parasitic properties, as the fungi of f avus, herpes, and thrush. 

 Injurious kinds among the real yeast fungi are unknown. 



PENICILLIUM GLAUCUM. 



Let us now turn to a species of the fungi. 



The most widely diffused among the mould fungi is the Penicil- 

 lium glaucum, whose green, dense films are found everywhere. 

 Wherever a " moulding " of any substance occurs, a Penicillium 

 glaucum will generally be found. Investigation of ^ir proves 

 that the germs of this fungus are present everywhere. 



Penicillium does not thrive at breeding temperatures and is, 

 therefore, destitute of pathogenic properties. 



Its colonies appear on the plate as whitish flakes which rap- 

 idly increase in size and become covered from the centre with a 

 superficial green, indicating sporulation. The gelatin is soon 

 liquefied around the colonies. 



The peculiar little brushes formed by the hyphae can be seen 

 even under low powers. 



On bread-paste a low, fine-flaked film of a white color forms 

 at the beginning, but soon turns decidedly green. 



Among the aspergilli, the non-pathogenic albus and glaucus 



