88 THE PHYLOGENY OF THE GENUS BRACHIOMONAS 
In the asexual reproduction of C. caudata, Wille describes 
the division as longitudinal, after the disappearance of the cilia 
of the mother cell, resulting in the formation of four zoospores. 
On several occasions when I examined material with my travel 
microscope in the field in late afternoon, or freshly collected 
material in early evening, I found numerous individuals which 
contained the four fully formed zoospores while the mother. 
cell was still swimming actively. It was only in the more rarely 
seen divisions of material kept for a day or two after collection 
that I found non-motille cells in process of reproduction; such 
cells may have lost the power of movement earlier because of 
poorer aeration than in the normal habitat. This division of 
actively motile cells I have found to be ‘normal in several other 
species of Chlamydomonas. I was unable to find examples 
which would actually show more of the details of the process 
of division than indicated by Wille, who merely furnishes one 
figure of completed division. I did, however, observe that a 
large majority of cases showed two of the daughter cells with ° 
their anterior end directed forwards, and two with the anterior 
end directed backwards (Fic. 49). In other species of Chlamydo- 
monas such as arrangement of the daughter cells is character- 
stically found when the first plane of division appears transverse 
to the longitudinal axis of the mother cell, or when, though 
fundamentally longitudinal, the plane becomes placed trans- _ 
versely by a rotation of the entire protoplast. During the 
past season I have had the opportunity of observing this 
latter method many times ina new species to be described in a 
future paper: this species furnished one exceptional case in 
which both divisions, carefully followed, were strictly longi- 
tudinal, resulting in four zoospores all headed toward the 
anterior end of the mother cell. This exceptional arrangement 
I also found in rare instances in C. caudata (Fic. 50). Wille’s 
figures (15, pi. 3, f. 8) which shows the same arrangement, 
appears, therefore to be untypical, and I am obliged to believe 
that the first division of this species, though properly longitudi- 
nal, would regularly show as a transverse cleavage, in consequence 
of a rotation of the protoplast to such an extent that its anterior 
pole comes to lie in a position nearly in the middle of the length 
of the cell. 
Reichenow (9, 10, pp. 35-39) it is true, has expressed the view 
that the division in all species of Chlamydomonas may be funda- 
mentally Jongitudinal, an apparent transverse division being al- 
