Phases of Evolution and Heredity

Next he discusses biometry as founded in Britain by Galton and as advanced by Karl Pearson, and he attributes great credit to the work of these men. To Semon, the author of Mnemism, Dr. Hart refers without immoderate criticism, but he suggests that the engram theory is as hypothetical as any of the suppositions of scholastic philosophy. He next proceeds to describe what is meant by mutation, but he makes no original suggestions as to its causation. Having thus shortly surveyed the more salient points in the teachings of the different schools of heredity, Dr. Hart goes on in Chapter VII to the important question of heredity in disease, and in this connection he finds consolation in the " purity of the strain in the germ cell and its non-affection by the soma," which accounts for the fact that many diseases formerly thought to be hereditary are not so. This little book constitutes a short survey of the views