Page:George Archdall Reid 1896 The present evolution of man.djvu/342

330 Were that so a race that was introduced to alcohol would become, other things equal, increasingly drunken in successive generations, exactly as if by the transmission of acquired traits, for in such a case the son would inherit the father's craving plus an increment to it, caused by the presence of alcohol in the fluids that bathed the father's germs, and would therefore drink more; the grandson would inherit the son's increased craving, plus a further increment caused by the more drunken habits of the latter, and would in consequence drink still more; so also as regards the great-grandson and subsequent descendants, till, in the presence of alcohol, the race would become more and more unfit, and would ultimately suffer extinction. But, as we have seen, races longest familiar with alcohol manifest the least craving for it, and therefore, à posteriori, we have every reason for believing that alcohol does not so affect the germs as to cause, in the individuals which spring from them, a craving for alcohol greater than would otherwise arise. When, therefore, a drunken son succeeds a drunken father, we must conclude that his tendency to excess is due solely to the inheritance of an inborn trait, and not to the inheritance of an acquired variation, nor yet to any effect produced by the poison on the germ whence he sprang. But since a fœtus has nervous structures, drunken habits in a pregnant woman may affect her unborn child, in such a manner as to render the individual into which it subsequently grows more drunken than he would otherwise be. But even in such a case, it is probable that the resulting variation is not of such importance as is commonly supposed; since between the birth of the affected individual and his arrival at an age when, under the ordinary conditions of society, indulgence is possible, so long an interval occurs that the variation is probably entirely lapsed.