Compositae.—Plants in which the inflorescence consists of numerous small flowers brought together into a dense head, the base of which is enclosed by a common envelope (e.g. the Daisy, Dandelion, &c.).
Congenital characters.—See Plasmogenetic characters.
Conjugation.—This term is applied to a process observed in the Protozoa (q. v.), which seems to correspond to the sexual reproduction of the Metazoa (q. v.). The majority of the Protozoa cannot long continue to reproduce themselves a-sexually without becoming degenerate, or rather without becoming altogether extinct. Two individuals (as a rule) consequently unite either temporarily or permanently. In the former case, an exchange of material is effected; and in the latter, complete fusion takes place.
Correlation.—The normal coincidence of one phenomenon, character, &c., with another.
Cytoplasm.—See pp. 30 and 32.
Determinant.—See p. 123.
Ectoblast.—Syn. of epiblast and ectoderm. The general result of the division of a fertilized ovum is a two-layered ball of cells (a gastrula). The outer layer is called the ectoblast and the inner layer the entoblast. (See Darwin and after Darwin, p. 137 et seq.).
Embryology.—Hence embryogenesis, &c. The study of the development or the early growth of the individual.
Entoblast.—Syn. of hypoblast and endoderm. See Ectoblast.
Epigenesis (Harvey).—The theory that organisms are formed by the development of the egg itself, and not by the expansion of a miniature within the egg (preformation).