156 LEVINE: CyTOLOGY OF HYMENOMYCETES 
The first division usually takes place in the upper part of the 
basidium, although the prophase stages begin while the nucleus is 
still near its center. The chromatin strands combine to form 
a long slender thread which forms a more or less irregular coil fill- 
ing the nuclear cavity. The chromatin filament may become quite 
thick and thus resemble a post-synaptic spirem (PL. 6, FIG. 19, 20; 
PL. 7, FIG. 71; PL. 8, FIG. 50). I also found a parallelism of the 
spirem strands which suggests splitting (PL. 6, FIG. 21). My figures 
of these stages show a close resemblance to those of Fries (1911') 
for Nidularia pisiformis. The spirem now becomes segmented as 
shown in FIG. 22, PL. 6, and each — soon perigee os shorter and 
denser. The number of these chr tly varies 
and it is very difficult to count them. During yee division 
a large vacuole appears at the base of the basidium. The nu- 
cleus moves toward the apex of the basidium and the spindle figure 
appears. The nuclear membrane disintegrates and the chromo- 
somes are found lying in a faintly blue-stained fibrillar spindle 
whose axis is transverse to the longitudinal axis of the basidium 
(PL. 6, FIG. 23). The nucleole is found in the cytoplasm (PL. 8, 
FIG. 52, 53). In some of my preparations the nuclear membrane 
and nucleole seem to have disappeared before or soon after the 
spindle is formed, while in others both are present at the equa- 
torial plate stage (PL. 8, FIG. 51). The direction of the long axis 
of the spindle in the division of the primary nucleus in the Boleti ; 
does not always conform to the generally accepted view as em- _ 
phasized by Juel (1897) and others. I found that while the 
transverse position is common there are many cases in which the 5 
primary spindle may be very decidedly inclined, at least seventy : 
degrees to the transverse axis of the basidium (PL. 7, FIG. 62). 1°@ 
have observed such cases in Boletus granulatus, B. chrysenteron, 
B. badius, B. alutarius, and B. albellus. The poles of the spindle 
end in small red-stained centrosomes from which long streaming 
rays extend to the center of the basidium (pL. 8, FIG. 51, 53) 
The appearance of the polar asters agrees well with that shown 
by Maire (1902) for B. regius. The cones of astral rays as seen 
in section resemble diminutive comet tails. The degree to which — 
the rays are developed depends upon the position of the pole in 
the basidium. If the pole lies on the wall few or no rays are visible. 
Vo tA) ie 
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W 
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