1915] BURLINGAME—ARAUCARIA BRASILIENSIS 3 
cells have reached the archegonium. The body cell is commonly 
surrounded by a very faint membrane (figs. 3 and 6). In some 
cases this membrane is either absent or so faintly marked as to be 
exceedingly difficult of observation. The line of demarcation 
between the two male cells is in most cases not well defined. There 
does not appear to be a distinct membrane even when the two 
masses of cytoplasm are seen to be clearly separable. These male 
cells are not organized in definite cells as they are in cycads and 
inkgo. 
At the time of division the two nuclei are of approximately 
equal size. They may both develop in similar fashion and share 
the cytoplasm equally (figs. 3 and 4), or one of them may degen- 
erate even after the partial division of the cytoplasm. Fig. 6 shows 
a male cell or sperm clearly bounded by a limiting membrane and 
with the nucleus at one extremity. Across it may be seen the faint 
line of demarcation between the two original cells. One nucleus 
has degenerated and only the faintest trace of it can be distin- 
guished in the tail opposite the functional nucleus. This degen- 
eration is probably fairly common, for one often finds unusually 
large male cells in tubes in which no trace of the other one can be 
found. It is possible, of course, that it has retreated up the 
tube and into the extra-nucellar portion and so escaped obser- 
vation. I incline to the opinion, however, that it has either 
degenerated or slipped out of the cytoplasm and become so 
reduced in size as to be indistinguishable from the prothallial and 
other nuclei. 
In a previous paper (3a) it was stated that these male cells 
might possibly be motile. Since then many tubes have been dis- 
sected out in sugar solution in the attempt to prove this. The 
results have been entirely negative. They are apparently amoe- 
boid (as for that matter are the male cells of some angiosperms), 
but there are no structural evidences of locomotor organs of any 
sort, nor were any rapid movements of any kind observed. Fig. 5 
shows a binucleate body cell rounding a sharp corner of the pollen 
tube at the point where it turns back into the nucellus after having 
crept along over the surface of the stale. The distortion in shape is 
not in any way due to crowding, for there was abundant room for 
