46 Farmer .- — • Studies in Hepatic ae : 
base of the sporogonium. The lining superficial cells of the 
lower part of the stalk and swollen base are remarkable in the 
richness of their protoplasmic contents, and in the large size 
of their nuclei. They perhaps play a part, not merely passive, 
in the absorption of food from the gametophyte. 
The capsular portion of the sporogonium originates from 
the uppermost cell, but as the sporogenous cells and the wall- 
layer are not differentiated until somewhat late, it is possible 
that the upper discs, into which the middle of the three first 
cells falls, may also contribute a share in the formation 
of this part of the sporogonium. Divisions in the young 
capsule are by no means regular, but eventually the 
tissue which ultimately goes to form the spores and elaters 
becomes clear, by the relative richness of its cells in 
protoplasm. 
In the young stages of the development of the sporogonium, 
instances of nuclear division are not unfrequently to be met 
with, and a striking difference is at once seen between these 
nuclei and those, already described, of the gametophyte. In 
the first place the sporophytic nuclei are relatively large, but 
the important difference lies in the fact that there are not 
four, but eight chromosomes, also of a looped shape, to each 
nucleus. Even a profile-view awakens a suspicion that the 
chromosomes, when in the equatorial plane, are more numerous 
in these nuclei than in the above mentioned gametophytic 
nuclei, and a view from the pole of the spindle amply con- 
firms this. Fig. 34 illustrates such a view, and it will be seen 
that there are, in all, thirty-two dots shown, sixteen lightly, 
and sixteen darkly, shaded. 
As a matter of fact this nucleus is in the diaster-stage, and 
the daughter-chromosomes are beginning to move apart. 
Those marked more lightly represent the ends of the retiring 
loops of one nucleus, whilst those shaded darkly belong to the 
loops of the other one. The chromosomes form U-shaped 
bodies here, and hence there are in reality only eight chromo- 
somes to each nucleus, the double number (sixteen) being due 
to the fact that the loops are seen in the direction of the 
