The cell is essentially an individualized mass of protoplasm containing a differentiated protoplasmic body, called a nucleus.
The conjoined organism is, in fact, a colony or association of the protoplasmic tinits, though each unit retains its independence.
Every plant is thus found to be composed of a number of these protoplasmic units, or, as they may preferably be termed, proloplasts, all of which are at first exactly alike in appearance and in properties.
Two features which are essentially protoplasmic assume a great importance when we consider these relations.
Communication between the various protoplasts of the colony is, however, carried on by means of fine protoplasmic threads, which are continuous through the cell-walls.