160 LEVINE: CYTOLOGY OF HYMENOMYCETES 
(PL. 5, FIG. 42). I have seen division figures in the spores of Boletus 
castaneus, B. albellus, B. punctipes, B. cyanescens, B. indecisus, B. 
glabellus, B. granulatus, B. chrysenteron, B. spectabilis, B. bicolor, B- 
griseus, B. subtomentosus, B. badius, and Strobtlomyces strobilaceus. 
The equatorial plate and subsequent stages come out very clearly 
and well-developed polar asters are present. Long astral rays can 
be seen radiating from the centers and extending to the ends of 
the spore (PL. 7, FIG. 79). The spindles are very narrow, but show 
clearly in the cavity of the nucleus, the nuclear membrane being 
stillpresent. The chromosomes are sharply differentiated from the 
spindle fibers (PL. 5, FIG. 76) but are so small and so massed together 
that their numbers cannot be definitely counted. The position 
of the spindles is either transverse or parallel to the long axis of 
the spore. The central spindle stretches in the anaphases and 
the chromosomes come to lie on the walls on opposite sides of 
the spore (PL. 8, FIG. 43, 65). The two daughter nuclei show all 
the essential features of the nuclei in the basidium (PL. 8, FIG. 66). 
In the spore of B. albellus, a second division occurs. The spore 
(PL. 8, FIG. 67) becomes very long and the two spindles which 
appear are similar to those previously described. The spindles 
may lie parallel or at right angles to each other, the latter case 
is shown in FIG. 68, PL. 8, where one of a pair of spindles is repre- 
sented. Fic. 67, 68, PL. 8, show clearly that the number of 
chromosomes is greater than two, as held by Fries (1911) for the 
first division in the spore. 
In the late anaphases, the chromosomes are found at the 
poles and appear to be fused into one or two masses. The nuclei 
are reconstructed and four small daughter nuclei result. The 
division here is not apparently conjugate. The spindles at least 
are not paired side by side, though the divisions are simul- 
taneous. In many spores, I have found three nuclei (PL. 8, FIG. 
69). Two were small, while the third was larger and had prob- 
ably not yet divided. It seems probable that the condition found 
in these spores indicates the initial stage in germination. . 
The karyokinetic figures in the spores of these Boleti are very 
distinct and suggest that further study of young mycelia will 
make possible the settlement of the question as to the first appeat- 
ance of conjugate division and regularly binucleated cells. ‘ 
