Physiologic

Physiological (fiz-e-o-loj' '-ih, fiz-e-o-loj' 'ik-al). Pertaining to physiology; pertaining to natural or normal proce es, as opposed to those that are pathologic. P. Antidote, an antidote that neutralizes not by its chemic power, but through its effects on the system. P. Excavation, the funnel-shaped depre ion at the center of the optic papilla, at the bottom of which the retinal ve els enter;it varies in size and form, but always has sloping walls, which distinguish it from a pathologic excavation, exhibiting vertical or overhanging walls. P. Selection. See Evolution . P. Units of Herbert Spencer, in biology, hypothetic, complex, protean units, intermediate between chemic units and morphologic units or cells. They are supposed to po e a polarity or aptitude to aggregate in the form of the particular species of organism to which they belong, just as the molecules of a salt po e the intrinsic aptitude to crystallize in a particular way. The entire body is supposed to be composed of these units, making regeneration of lost parts po ible, while the germ cells are supposed to contain small groups of them, giving each germ-cell the power of reproducing the whole. The theory is one of epigenesis. See id, idant, idioplasm, plasome, micro somata, heredity, epigenesis, pangenesis, etc. Physio log ism (fiz-e-ol'-o-jizm). The abuse of physiology.