EREMASCACEAE IMPERPECTAE 



191 



tions into arthrospores whose ends never become rounded. The creamy cul- 

 tures are moist and shining at least in the first weeks, while the membranous 

 colonies are dry and dull. 



The characters of these tAvo major groups may be distinguished as follows: 



CREAMY TYPE 



Earely folded, only when the growth is very 

 rapid. 



Consistency of thick paste, easily adhering 

 to the needle but never viscid, easily 

 separating from the substrate. 



Yellowish or Ijrightly colored. 



Forming flocculent deposits in potato decoc- 

 tion but no pellicle. 



Giant colony thick, convex, surface smooth, 

 shining humid, uniform or with slight 

 furrows, center often conic, margins 

 lobulate. 



MEMBRANOUS TYPE 



Surface soon folded, soon velvety or studded 

 with coremia. 



Consistency viscid, not adhering to needle, 

 or if adhering drawing out in a long 

 thread, more adherent to the medium. 



Dull grayish white. 



Forming less coherent flocculent deposits on 

 potato decoction and usually a thick 

 highly developed pellicle. 



Giant colony thick, dull, flat folded, fur- 

 rowed, with coremia, margin not lobed. 



Two intermediate groups may be characterized in the creamy type. In 

 Mycocandida, the thickness of the colony is variable, surface smooth or curdled, 

 shining, or even iridescent, often transparent when young ; surface may be 

 somewhat folded, j'-ellowish white, growth slower and colony diameter less 

 than in the typical creamy type. In Blast odendrion colony thin and with deep 

 radial furrows with a central eminence, surface smooth and dull. 



The sprout cell or blastospore is the fundamental element of the creamy 

 group. In general, the shape is characteristic of the genus, but one may often 

 find many variations in a given culture (Fig. 39). They may be characterized 

 as spherical, short ellipsoid, long ellipsoid, ovoid, or long ovoid. (In examina- 

 tion of material one should be sure that the cells have their longest axis ap- 

 proximately at right angles to the line of vision, or a long ellipsoid cell may 

 appear short ellipsoid or even subspheric.) Then we have an asjanmetrical form 

 in Geotrichoides, an intermediate genus with membranous colonies. The pyri- 

 form type (stalagmoide) often suggesting drops or tears is characteristic of 

 Blast odendrion. Of the elongate types, cylindric and clavate are common. 

 Sometimes they are somewhat irregular in development, producing allantoid and 

 other irregular shapes. 



The various stages in the development of the cell have been clearly de- 

 scribed by Shrewsbury for Hansennla (Willia) , and probably his obseiwations 

 might be extended to the groups covered bj^ Langeron & Talice. The young cell 

 is small, ovoid, spherical, or allantoid with a thin wall and a refractile, homogene- 

 ous cytoplasm (Fig. 40, 1). Sprouting is active, the sprout cells being exactly 

 like miniature mother cells. In each a small refractile corpuscle is visible near 

 the center of the cell. The nature of this body is uncertain, as it could not be 

 identified in fixed preparations and was not stained by vital stains. 



As growth progresses, the young (adolescent) cell enlarges and the cyto- 

 plasm becomes more granular (Fig. 40, 2). Vacuoles appear, generally only 



