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Alga-like Organism. 
every cell would tend to move upward in a slightly different 
direction. However, the two lower cells resulting from the 
second division are usually so situated that they are left 
enclosed in compartments of the filament, while the two upper 
cells alone give rise to branches. 
With the above we have finished our description of the 
anatomy of the organism. As suggested at the beginning 
of the paper, the position of the form, whether plant or 
animal, is not easy to determine, and we must give our 
reasons for considering it related to certain forms that are 
usually called plants. But we must first consider some general 
features of its structure and mode of growth. 
The writer has used the term cell-cavity to designate the 
compartments of the filament in order to simplify the descrip- 
tion, but it seems to him, that the wall of the filament does 
not bear the same relation to the masses of protoplasm that 
a cell-wall of a plant usually does to its contents. We have 
seen that the protoplasmic masses are very variable in shape, 
sometimes having processes extending from their inferior ends 
sometimes contracted into a compact form with a regular 
outline, and that the one condition may readily change into 
the other. This mobility of the masses of protoplasm is 
associated with the peculiarities of the method of growth, 
and indicates that the protoplasmic masses maintain a degree 
of independence of their enclosing filaments that is not what 
we expect of the contents of plant-cells as a rule. 
The motile condition of the organism resembles in many 
ways the macrozoospores of chlorophyllaceous Algae. There 
are the four cilia, the pigment-spot, and the habit of coming 
to rest after a comparatively short period of activity, all of 
which characters are possessed by most zoospores. But in 
the non-motile condition the masses of protoplasm still retain 
the pigment-spot, a structure that is not generally present in 
the vegetative cells of Algae. The mobility of the protoplasmic 
masses and the fact of the pigment-spot being present in all 
stages of the cycle of development, suggests at once certain 
organisms of which Euglena may be mentioned as an example. 
