The purpose, or end they serve, I have, I think, sufficiently dealt with in my “Darwinism”; the method by which such useful tints and markings are produced, because useful, is, I think, clearly explained by the law of Natural Selection or Survival of the Fittest, acting through the universal facts of heredity and variation.

But the “why”—­which goes further back, to the directing agency which not only brings each special cell of the highly complex structure of a feather into its exactly right position, but, further, carries pigments or produces surface striae (in the case of the metallic or interference colours) also to their exactly right place, and nowhere else—­is the mystery, which, if we knew, we should (as Tennyson said of the flower in the wall) “know what God and Man is.”

The idea that “cells” are all conscious beings and go to their right places has been put forward by Butler in his wonderful book “Life and Habit,” and now even Haeckel seems to adopt it.  All theories of heredity, including Darwin’s pangenesis, do not touch it, and it seems to me as fundamental as life and consciousness, and to be absolutely inconceivable by us till we know what life is, what spirit is, and what matter is; and it is probable that we must develop in the spirit world some few thousand million years before we get to this knowledge—­if then!

My book, “Man’s Place in the Universe,” shows, I think, indications of the vast importance of that Universe as the producer of Man which so many scientific men to-day try to belittle, because of what may be, in the infinite!—­Yours very truly,

ALFRED R. WALLACE.

PART IV

Home Life

(By W.G.  WALLACE and VIOLET WALLACE)

In our father’s youth and prime he was 6 ft. 1 in. in height, with square though not very broad shoulders.  At the time to which our first clear recollections go back he had already acquired a slight stoop due to long hours spent at his desk, and this became more pronounced with advancing age; but he was always tall, spare and very active, and walked with a long easy swinging stride which he retained to the end of his life.

As a boy he does not appear to have been very athletic or muscularly strong, and his shortsightedness probably prevented him from taking part in many of the pastimes of his schoolfellows.  He was never a good swimmer, and he used to say that his long legs pulled him down.  He was, however, always a good walker and, until quite late in life, capable of taking long country walks, of which he was very fond.

He was very quick and active in his movements at times, and even when 90 years of age would get up on a chair or sofa to reach a book from a high shelf, and move about his study with rapid strides to find some paper to which he wished to refer.