144 



MEDICAL MYCOLOGY 



Growth good at both room temperature and at 37° C. On fluid media 

 cells citriform or ellipsoid, 5.2 x 2.4/*. In old cultures a slight tendency to- 

 ward "mycelium" formation. Vegetative development by sprouting. No 

 trace of sexual process, spores normally 4 per ascus, cucuUate, becoming 

 spherical on germination. A tubelike protuberance is put out which leaves 

 the spore and takes on the characters of the ordinary* vegetative cell. While 

 sexuality has disappeared there is evidently some physiologic differentiation 

 of the spores. After mordanting with chromic acid, staining with carbol- 



Fig. 22. — Dipodascus albidus. 1, 2, young copulation branches not yet abjointed ; S, h< 

 diploid nucleus in female copulation ; 5, first step in division of diploid nucleus ; 6, later stage ; 

 7, 8, later stages of young ascus ; 9, upper portion of nearly mature ascus, the dark points in- 

 dicating degenerate nuclei. (i, 2, 5-9 X900 ; 3 X800 ; 4 X600.) (After Dangeard 1907, 

 Juel 1902.) 



fuchsin, decolorizing with sulphuric acid, and counterstaining with methylene 

 blue, the equatorial pair of spores were acid-fast while the polar pair were 

 blue. 



Giant colonies on malt agar, grayish brown, edge lobulated, surface 

 smooth showing very delicate concentric rings corresponding to the days of 

 growth, no radial lines, a central knob present from the beginning and later 

 secondary knobs appear at various places. 



