XI, B, 6 Wade: Cultivation of a Pathogenic Fungus 273 



delicate, robin's-egg blue and the metachromatic granules and 

 masses, usually of a clear red, are prominently in contrast. This 

 type of cell develops into the leucocytelike form, with or without 

 protoplasm. 



DEVELOPMENT OF PARASITIC FORMS ON MEDIA WITHOUT FREE BLOOD 



In tissue scrapings planted on ordinary media without smeared 

 blood there occur forms of early multiplication, most of which 

 might well be mistaken for products of degeneration of inocu- 

 lated tissue. In smears stained by Gram's there is often to be 

 seen only amorphous material containing a few Gram-positive 

 granules and small, round, or oval bodies (fig. 15). There often 

 are more or less numerous small masses (8 to 12 microns in 

 length) , which may be either body or parasite cells (fig. 16) that, 

 because of their rather hyaline, amorphous appearance, may be 

 mistaken for fragments of debris. In some of these cultures the 

 large gelatinous forms appear, but these are not constantly found. 



Multiplication of the organisms in these cultures persists only 

 so long as there is tissue substance present; consequently the 

 organisms soon die out. 



DEVELOPMENT IN PLANTED TISSUE BITS 



Here the parasitic forms sometimes enlarge and quickly pro- 

 duce hyaline spore-granules. Often, however, they are trans- 

 formed into the very much larger, gelatinous-appearing masses 

 noted, which have developed fully only within pieces of planted 

 tissue. These may be unstained and scarcely recognizable after 

 Gram's stain (fig. 17). 



Gelatinous bodies. — In an occasional preparation one may trace 

 the transition of the basic form to small gelatinous bodies (fig. 

 26) and the enlargement of these. In some cultures those of 

 medium size seem firm and stain deeply, as though the contents 

 were thick and gelatinous, though in more instances they appear 

 to be softer. 



Under some conditions the gelatinous bodies develop vast num- 

 bers of the small, hyaline spore-granules. At other times the 

 spore-granules and deeply staining basic forms, often very small, 

 develop simultaneously. The latter at times appear in large 

 numbers, with or without the hyaline granules. In fig. 28 is a 

 group of basic-form bodies which developed from such a gelati- 

 nous mass as shown in fig. 27. In fig. 29 is an unusual group 

 of closely packed "gelatinous" forms, now thin and vesicular, 

 all of which contain numbers of the basic granules and bodies. 



The most favorable condition for this development is cultiva- 



