502 Farmer , — On Spore-Formation and 
pania , that It seems reasonable to conclude that both have 
passed through a similar history. The chromosomes are 
much smaller. The same curious prophase was seen in this 
plant as has been described for Scapania , but it is not so 
obvious owing to the smaller size of the cells, and still more, 
to the increased number of the chromosomes. In the mature 
spindle there are about eighteen chromosomes, and as they 
are very small, it is exceedingly difficult to follow out the 
minute details. This much is however certain, that they con- 
sist of flattened rings, and that they divide across the middle, 
thus serving as another example of a heterotype mitosis. 
The second division is exactly like the first, and both differ 
markedly from the divisions which obtain in the gametophyte. 
I did not see any mitoses in the archesporial cells. 
Lophoeolea bidentata and L. ciliolata. 
The same features which characterize Scapania are also 
met with in Lophoeolea , but in some respects the latter is 
a more advantageous object than the former, inasmuch as the 
spore-mother-cells mature more gradually, and thus several 
stages may often be made out in one preparation. The 
lobing of the mother-cell is a little more marked than in 
Scapania ; the nucleus is situated, in both groups, in the 
centre of the iobed cell. It seems, however, a singular fact 
at first sight that the quadripolar spindle; so striking in 
Scapania , is difficult to distinguish here, although the tetra- 
hedral shape of the nucleus becomes plain enough. I do not, 
however, attach very much importance to this, as experience 
shows that the stages at which this form of spindle is clearly 
recognizable may be very transient, and that in this respect 
much variation is shown amongst even closely allied forms. 
The nucleus, during the earlier period, consists of a slightly 
staining ground-substance, which surrounds the nucleolus. 
This body stains sharply and intensely, but later on, It 
becomes vacuolated, and stains far less readily. This change 
occurs simultaneously with the initial differentiation of the 
chromosomes. These bodies originate as granular areas, each 
