88 BOTANICAL GAZETTE JAUGUST 
suspensors. The entire endosperm tissue is multinucleate, a condi- 
tion which begins to appear while the archegonia are young; it results 
from the failure of walls to form. In the older endosperm as many 
as eight nuclei occur in a cell. The megaspore membrane at the 
fertilization period is about 2.5 thick at the lower part of the 
prothallus, and about 4.5 # when the cotyledons appear (fig. 31). 
Before discussing relationships, it will be helpful to summarize 
the important facts about Phyllocladus, including the work of Miss 
ROBERTSON and Miss KILDAHL. 
SUMMARY 
1. The stamen bears two abaxial sporangia. 
2. The pollen grains have two wings. 
3. In the male gametophyte there are two prothallial cells; the 
first usually disappears, the second occasionally divides. 
4. The generative cell divides anticlinally but obliquely, and the 
stalk cell partially encircles the second prothallial and body cells. 
5. The mature pollen grain contains the body cell and the free 
stalk, prothallial, and tube nuclei. 
6. There are two unequal male cells, only the larger of which 
functions. 
7. The ovulate structure is a strobilus with a single erect ovule 
in the axil of each scale. 
8. A symmetrical arillus originates from the base of the ovule and 
remains free from the integument. 
g. The outer fleshy layer is represented by two layers of cells. 
10. The nucellus is free to the base. 
11. The megaspore mother cell gives rise to a row of three cells, 
the innermost of which is the functioning megaspore. 
12. The spongy layer and megaspore membrane are strongly 
developed. 
13. Each ovule contains two archegonia, occasionally three OF 
four, each with its own jacket, but sometimes there is a complex ° 
two in a common jacket. 
14. The neck of the archegonium consists of four cells in a plate; 
occasionally these divide anticlinally. 
15. There is a ventral canal nucleus. 
