traits acquired under the influence of alcohol are also not transmissible. But as regards the evolution that has been produced by alcohol, just as regards the evolution that has resulted from disease, we have abundant reason to conclude on à posteriori grounds also, that no part of it has resulted from the accumulation of acquired traits; for were the acquired effects of alcoholism transmissible, i.e. were that part of the craving for alcohol, that increase of it which results from the indulgence in the poison, transmissible, then races that have had the most extended experience of alcohol should, of course, crave most for it, and be the most drunken. The contrary, however, is the case, for races that have long been familiar with it are conspicuously temperate, whereas races which have had little or no familiarity with it are conspicuously intemperate when opportunity is afforded for indulgence.
The evolution against alcohol has therefore resulted solely from the accumulation of inborn variations through the survival of the fittest. To prevent any misapprehension it should be noted, however, that alcohol, like disease, has not directly, but indirectly only, been the cause of evolution. It has been a factor of elimination, not of survival. Those individuals whom it has greatly affected have tended, other things equal, to perish and leave no offspring, whereas those whom it has affected little or not at all, have tended to survive and continue the race. In this it differs from a beneficial agency such as food, which, since it is a factor of survival, not of elimination, is a more immediate cause of evolution.
Even more than disease alcohol has been supposed to furnish a case of the transmission of acquired traits. Among the vulgar, who commonly repudiate the theory of evolution, the belief is universal that an indulgence in alcohol by the parent tends to result in a craving for it in the offspring greater than would otherwise arise,
