1914] BURLINGAME—ARAUCARIA BRASILIENSIS 501 
of a slightly sticky liquid between the sporophylls, but I failed to 
find any evidence that it comes from the nucellar tip. 
At about the time the walls are formed in the peripheral parts 
of the gametophyte, in the latter part of February usually, the 
archegonium initials become recognizable. Owing to their scanty 
contents they are recognizable only after they are somewhat 
enlarged. They vary in number from about 6 to 15 or more. 
They are situated in a ring around the crown of the prothallus. 
They do not all mature at the same time, though there does not 
appear to be any regular order. Commonly 5-8 mature and 3 or 
more of these are frequently fertilized. Within the circle the indi- 
vidual archegonia may stand alone (fig. 4) or they may be grouped 
in complexes (figs. 30, 44). Each archegonium is commonly sur- 
rounded by an individual jacket, though in some of the complexes 
there may be no cells at all between some of them (fig. 44). 
The initial is commonly a wide U-shaped (fig. 31) or V-shaped 
(fig. 32) cell. It has a large nucleus and little cytoplasm. Some- 
times a basal cell is cut off from this cell (fig. 33) before it becomes 
the actual initial. The nucleus of the initial divides and a peri- 
clinal wall separates a thin flat primary neck cell from the inner or 
central cell (figs. 32, 34, 37). The central cell enlarges much more 
rapidly than the neck cell (figs. 38-40). The latter soon divides by 
an anticlinal wall. This division is more frequently in the direction 
of its greater diameter. Each of the halves then divides into about 
6 wedge-shaped cells. The nuclei of these wedge-shaped cells are 
invariably at the large end of the wedge. The points of the cells 
meet or nearly meet at the center of the neck. At this point the 
cells have commonly thinner walls, less cytoplasm, and a tendency 
to separate and leave a free passage to the egg (fig. 46). Viewed 
from above, the group of neck cells has either a rounded (fig. 46) 
or elliptic (fig. 47) outline; from the side they usually appear as a 
dome or cap (fig. 45). 
Many variations in the form and outline of the neck occur. 
The size of the group as well as the number of cells in it is subject 
to considerable variation. The commonest arrangement is 12 cells 
arranged in a single tier (figs. 45, 46). Figs. 48-50 show three serial 
sections through a neck in which there is one extremely large cell. 
