THE SPOROPHYTE OF SPHAGNUM SUBSECUNDUM 297 
in the venter of an archegonium ready for fertilization is ovoid or somewhat 
pear-shaped, and shows clearly a nucleolus with a nuclear body (hisTaf. II, 
fig. i). The fertilized egg is drawn very indefinitely, and no description is 
Fig. I. Embryo of 2 cells. Fig. 2. Embryo of 4 cells. Fig. 3. Embryo of 4 
primary segments. Apical cell much elongated, probably preparatory to division. Basal 
segment has divided irregularly. Fig. 4. Embryo of 5 cells, showing cytoplasmic details 
at this stage. Fig. 5. Embryo of 6 cells. All X 300- 
given save that it is surrounded by a hyaline mass of slime (Taf. II, fig. 2). 
The fertilized egg divides transversely, the upper half being the apical cell. 
A two-celled embryo is drawn in which the upper cell is relatively small as 
compared with the basal segment. Waldner states that the apical cell, by 
walls parallel to its base, cuts off a series of segments from 6 to 8 in number. 
The basal cell makes only a few irregular divisions and does nothing more. 
Waldner's figures show that the wall separating the basal and apical seg- 
ments is sharply defined and may be followed for some time in the subse- 
quent stages of development of the young sporophyte. 
Fertilization, and the Development of the Young Sporophyte 
After a number of attempts, fertilization was brought about in the 
laboratory by squeezing the heads of antheridial plants and immediately 
allowing the exuding liquid to drop on the tips of archegonial plants 
which were almost entirely submerged in water. A detailed account of 
these experiments may be published at some later date. Unfortunately, 
