their plasmodomous or plasma-forming sisters. This is the first instance of the great principle of division of labour.
2. The second stage is that of the simple and single cell, a bit of protoplasm with a nucleus. Such unicellular organisms are still very common. The Amœbæ are their simplest representatives. The morphological value of such beings is the same as that of the egg of any animal. The naked egg cells of the sponges creep about in an amœboid fashion, scarcely distinguishable from Amœba. The same remark applies to the egg-cell of man himself in its early stages before it is enclosed in a membrane. The first unicellular organisms arose from Monera through differentiation of the inner nucleus from the outer protoplasm.
3. Repeated division of the unicellular organism produces the Synamœbium, or community of Amœbæ, provided the divisional products, or new generations of. the original cell, do not scatter, but remain
