Sec. 19. Reproduction, its Phenomena
All the phenomena of reproduction may be grouped under the following heads: (1) Production of the spermatozoön, (2) production of the ovum, (3) their fusion into the fertilized ovum, (4) production of daughter-cells, (5) distribution, mechanical arrangement and grouping of cells, (6) differentiation of cells into the different tissues, (7) waste of cells.