HYPHOMYCETES 547 



are doubly contoured and form chlamydospores. If a bit of the 

 membrane be macerated in a drop of acetic acid the epithelial cells 

 are cleared and the parasite is readily observed. Two distinct types 

 are recognizable in gelatin cultures, one of which liquefies the medium, 

 the other does not. In solid media yeast-cell formation predominates 

 and many of the cells are observed to bud; in fluid media mycelia 

 are produced and spore-formation usually occurs after several days' 

 incubation. The spores chlamydospores usually enlarge and 

 develop into filaments when they are transplanted into fresh media. 

 The organism is not uncommon in the air. 



The organism does not produce thrush when introduced into 

 experimental animals, but it may cause a generalized thrush mycosis 

 when injected intravenously in rabbits. 



FIG. 87. Sporothrix. 



Asperyillm Mycosis. Aspergillus fumigatus occasionally incites 

 a disease of the lungs and bronchi in birds and rarely in man. The 

 organism penetrates to the alveoli and the mycelia and spores may 

 be demonstrated in sections of the lungs in fatal cases. It also has 

 been found rarely in middle-ear infections and in the nasopharynx. 



The mold grows readily upon ordinary media and the colonies, 

 after several days, become dark green in color. The organism belongs 

 to the genus Aspergillus, which is widely distributed in damp cellars 

 and upon food. Microscopically, aerial hyphae arise from the fila- 

 mentous mycelium, whose distal ends are swollen into club-shape 

 masses of undivided sterigmata, from which chains of conidia arise. 

 The conidia are spherical, greenish, and measure about 3 microns in 

 diameter. It is differentiated from many of the aspergilli by its green 



