Further consideration tends to obliterate this supposed distinction. Although Wallace used the term “variety” as contrasted with “species,” the whole context proves that he, equally with Darwin, recognised the importance of individual variations and of variations in single characters. This becomes clear when we remember his argument about the neck of the giraffe, the changes of colour and hairiness, the shorter legs of the antelope, and the less powerful wings of the passenger pigeon. Wallace has kindly written to me (May 12th, 1896) stating the case as I have given it, and he further explains-- “I used the term ‘varieties’ because ‘varieties’ were alone recognised at that time, individ^l variability being ignored or thought of _no importance_. My ‘varieties’ therefore included ‘individual variations.’” On the other hand, Darwin certainly included large single variations (in other words, “varieties”) as well as ordinary individual differences, among the material for natural selection, and he did not abandon the former until he was convinced by the powerful reasoning of Fleeming Jenkin (_North British Review_, June, 1867), who argued that single large differences of a sudden and conspicuous kind (Darwin’s “variations”) would certainly be swamped by intercrossing. Upon this review of the “Origin” Francis Darwin says (“Life and Letters”)-- “It is not a little remarkable that the criticisms which my father, as I believe, felt to be the most valuable ever made on his views should have come, not from a professed naturalist but from a Professor of Engineering.” After reading this review, Darwin wrote to Wallace (January 22nd, 1869):-- “I always thought individual differences more important than single variations, but now I have come to the conclusion that they are of paramount importance, and in this I believe I agree with you. Fleeming Jenkin’s arguments have convinced me.” The ambiguity of this sentence evidently misled Wallace into believing that the single variations were considered of paramount importance. Darwin therefore wrote again (February 2nd):-- “I must have expressed myself atrociously; I meant to say exactly the reverse of what you have understood. F. Jenkin argued in the ‘North British Review’ (June 1867) against single variations ever being perpetuated, and has convinced me, though not in quite so broad a manner as here put. I always thought individual differences more important; but I was blind and thought single variations might be preserved much oftener than I now see is possible or probable. I mentioned this in my former note merely because I believed that you had come to a similar conclusion, and I like much to be in accord with you. I believe I was mainly deceived by single variations offering such simple illustrations, as when man selects.”