170   Life and Letters of Francis Galton

heritance of acquired characters. This position, which is clear cut and fairly easily defensible, was I hold later obscured in his mind by two influences (a) the strong belief of Darwin in the inheritance of acquired characters, and (b) Darwin's doctrine of pangenesis. Both may be summed up in the single influence : an intense admiration for Darwin, which enforced an exaggerated respect for the authority of his judgment in individual instances. The doctrines of pangenesis and of the inheritance of acquired characters seem to me to have actually retarded Galton's progress and to have rendered his statement of his own views less clear than they otherwise would have been. I trace this influence particularly in his paper 'On Blood-relationship' of 1872'. This memoir would, I think, have given a sharp-cut theory had it not been darkened by the shadow of Darwin's views on heredity.

We will cite in regard to this the opening words of the 'Blood-relationship':

"I propose in this memoir to deduce by fair reasoning from acknowledged facts, a more

definite notion than now exists of the meaning of the word 'kinship.' It is my aim to analyse and describe the complicated connection that binds an individual, hereditarily, to his parents and to his brothers and sisters, and therefore, by an extension of similar links, to his more distant kinsfolk. I hope by these means to set forth the doctrines of heredity in a more orderly and explicit manner than is otherwise practicable.

From the well-known circumstance that an individual may transmit to his descendants ancestral qualities that he does not himself possess, we are assured that they could not have been altogether destroyed in him, but must have maintained their existence in latent form. Therefore each individual may properly be conceived as consisting of two parts, one of which is latent and only known to us by its effects on his posterity, while the other is patent and con

stitutes the person manifest to our senses." (p..394.)

Galton then proceeds to say that both these patent and latent elements in the parent give rise to the 'structureless elements' in the offspring. Now in the above sentences Galton clearly divides the 'structureless elements' of the parent into those which give rise to the somatic characters of the parent, and those which remain latent. At first sight we might suppose from the above definitions that Galton did not include latent elements similar to those which produced the somatic characters, but it appears from his remarks on p. 398 that he really did so, for he attributes on that page special features in the offspring corresponding to special features in the parents, not to the somatic characters in the parents, but to `latent equivalents.' In other words, he considers that, in the bulk of cases, the correspondence in somatic characters between parent and child is not due to any influence of the somatic characters of the parent, but results from the latent elements of the parent. Thus Galton's `latent elements' constitute absolutely the gametic elements of more modern notation. Had Galton gone at this time a stage further, and asserted that the somatic characters of the parent were only an index to the latent elements in him, and not directly associated with the bodily characters of the offspring, he would have reached an important principle. I hesitate to call that principle merely the continuity of the germ-plasm, for Galton saw a good deal further than anything contained in the word `continuity' itself. He believed that both in the case

1 Proc. R. Society, Vol. xx, pp. 394-402.