CYTOLOGY OF EOCRONARTIUM MUSCICOLA 
drawn out into a long, irregular, deep-staining rod in order to effect 
its passage through the narrow canal between the sterigma and the 
spore. No evidence is given to indicate that the centrosomes function 
in directing the nucleus into the sterigma or in pulling it into the spore. 
The elongate rod after its entrance into the spore soon contracts into 
a globose, homogeneous, deep-staining mass which later takes on the 
usual appearance of a globose resting nucleus. 
15. The spore is liberated from the basidium in the uninucleate 
condition. Germination in wet weather frequently occurs at once on 
the sporophore. The spores may be induced to germinate in nutrient 
solutions and on solid media. In germination the cytoplasm and 
nucleus pass out into a germ-tube, but the nucleus never undergoes 
division there. There is no increase in the amount of cytoplasm, and 
septa are not formed. 
16. Nothing is known of that phase of the nuclear history which 
follows spore germination and precedes the appearance of the binucle- 
ated series of cells in the endophytic hyphae. Consequently the origin 
of the binucleate condition has not been determined. The difficulties 
which have been encountered in the investigation of this phase of the 
life cycle are discussed in the writer's previous paper on Eocronartium 
muscicola (12). 
Department of Plant Pathology, 
Cornell University 
BIBLIOGRAPHY 
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