1915] BURLINGAME—ARAUCARIA BRASILIENSIS 29 
cells. I should like to suggest that they strongly resemble a group 
of prothallial cells about a body cell or sperm as they appear in 
Araucaria. So far as it goes, it seems to me, the evidence is that 
there were prothallial cells in the paleozoic pollen grains, notwith- 
standing that eminent botanists have interpreted the evidence to 
the contrary (7). 
I have elsewhere (3a) called attention to the very large male 
cells of Araucaria, and Eames has recently (8) shown that they 
are present in Agathis also. A further peculiarity in their forma- 
tion is exhibited by Araucaria brasiliensis, in that the division of 
the body cells occurs a long time before fertilization and not about 
simultaneously (7) with the division of the central cell a few days 
before fertilization. This division usually occurs outside of the 
nucellus a month or even two months before the pollen tube has 
actually reached the archegonia. Not only are the male cells long- 
lived, but they appear to be more active and independent than 
those of most conifers. This appears to me to be a primitive and 
unspecialized behavior, and one that would be unlikely to be 
derived secondarily from the condition now obtaining in the pines. 
The male cells of Araucaria pass through the neck of the arche- 
gonium without injuring it. CourreR and CHAMBERLAIN (7) 
assert that the pollen tube of the Pinaceae destroys the neck, 
though Lawson (12c) has recorded that the pollen tube of Sciado- 
pitys passes between the neck cells. Among the Taxaceae the 
neck cells are sometimes destroyed (Torreya, CouLTER and Lanp 
6), and sometimes the male cells pass through without injuring 
them (Phyllocladus, Miss Younc 26), just as in Araucaria. In 
Agathis (8) the male cells enter the top of the archegonium to one 
side of the neck cells, which are thereby broken loose from their 
anchorage to the jacket. In Podocarpus the necks appear to be 
broken through by the neck, though SrnNorr’s (21) statement is 
not specific as to whether the neck cells are destroyed or not. 
In Cephalotaxus (12b) the neck cells are probably destroyed by 
the entrance of the tube between them. In Cryptomeria, which 
externally resembles some species of Araucaria very closely and 
has other suggestions of affinity as well, the male cells are said 
(12a) to pass between the neck cells, but to injure them in doing 
