NUCLEAR DIVISION 25 
next in order. Even, therefore, if the spermatia could produce 
an infection, their feeble aid would be wasted at such a time of 
rejuvenation. 
(8) There is also to be considered the fact that the 
spermogones and spermatia of the Uredinales resemble those of 
the Collemacez, which have been shown by Stahl (1877) and 
Baur (1898) in all probability to fulfil the male function’. It 
may be pointed out, in this connection, that the great similarity 
of the spermogones to the pycnidia of the Ascomycetes has 
been too much ignored, and that its significance is not yet fully 
appreciated. In the Ascomycetes the pycnospores in most 
cases undoubtedly act as conidial forms, and have lost all traces 
of their primitive male function—in the Uredinales the sper- 
mogones have equally lost their function, but have not taken 
on the secondary réle of conidia: it may be suggested that the 
latter are otherwise well provided for in that respect, and hence 
feel no necessity for additional conidia. The spermatia of 
Polystigma rubrum are, however, functionless either as male 
cells or as conidia (Blackman and Welsford, 1912). 
NucLearR DIVISION IN THE UREDINALES. 
This is always of a simple type, not primitive, but reduced. 
The number of chromosomes seems to be always somewhat 
uncertain, and the chromatin forms masses which vary in 
number from one to four. In the ordinary vegetative division, 
which may be regarded as approaching rather to the nature of 
amitosis, the nuclear membrane disappears, the nucleolus is 
extruded, and the chromatin masses are drawn apart on a kind 
of rudimentary spindle to form the daughter nuclei. In syn- 
karya, the two paired nuclei in a cell are almost always in the 
same stage of division at the same moment, and the four 
resulting daughter nuclei move apart in such a way that the 
two nuclei in each daughter cell are never sister-nuclei (Hoff- 
mann, 1911). 
1 A remarkable instance in Collema, though outwardly not at all resembling 
the case of the Uredinales, is described by Bachmann (1912). 
