304 Woodbiirn. — Spermatogenesis in certain Hepaticae. 
does he find at this, or a later stage, the irregularly granular nature of the 
cytoplasm. The latter’s figures all show a very smooth homogenous cyto- 
plasm. At times (Fig. 28 a) I found the cytoplasm quite finely granular, 
but. as a rule, the structure was coarser and more irregular, the smaller 
granules tending to collect into larger masses. 
The chromatin then collects into one or more lumpy, irregular masses 
in the centre of the nuclear cavity. This latter now stains rather densely, 
as if filled with some homogenous or very finely granular substance. This 
appearance of the nucleus continues during the formation of the chromo- 
somes and the early stages of spindle formation. The two latter processes 
were not observed in detail, but Fig. 27 shows a chromatin mass, shortly 
before the differentiation of the chromosomes, still surrounded by the same 
darkly staining substance. This homogenous material around the chromatic 
mass seems to indicate a preparatory step in the formation of the spindle. 
The spindle fibres (Fig. 28) apparently occupy the former nuclear area and 
stain quite similarly to the homogenous nuclear content, so that it seems 
quite possible that the fibres have had their origin in this latter substance. 
If this be so, it agrees with the origin of the spindle in the spore-mother- 
cell of Pellia epiphyllia as described by Farmer (’95), with the exception 
that there are no centrosomes or centrospheres present (Figs. 28 and 28 a). 
There is nothing that indicates the presence of centrosomes, as claimed by 
Ikeno (’07) and Schaffner (’08) for similar spermogenous stages in the same 
plant. Fig. 28 shows two granules, or bodies, in the region of one pole, 
but the latter is broad, a condition that does not obtain when true centro- 
somes are present. Even when these bodies do chance to be in such 
a position, it seems quite arbitrary to designate them as bodies specially 
differing from others which occur just as frequently in various places 
throughout the cell. Usually no special body of any sort occupies the 
spindle pole (Fig. 28 a). So far my observations agree with those of Escoyez 
(’07), except that I did not find the spindle fibres forming definitely outside 
of the nuclear membrane as represented by his Figs. 13-15. 
The earlier mitotic conditions in the spermogenous cells of Fegatella 
are much the same as in Marchantia , but as metakinesis approaches there 
are some differences, so that a brief description will be in place. The 
nuclear figures are, as a rule, larger and more distinct. The nucleus in 
a resting condition (Fig. 45) shows a linin network with small lumps of 
chromatin quite evenly scattered throughout, and one or more relatively 
large, centrally placed bodies. Fig. 45, which is typical of this stage, shows 
one body which resembles a nucleolus, and another body which has the 
appearance of a mass of chromatin. The number of the larger bodies may 
vary from one to several. During prophase the chromatin becomes scattered 
rather evenly in the nuclear network as irregular Jumps of nearly uniform 
size (Fig. 46). From this condition an irregular spireme develops which is 
