A Malay and an American, although different, agree between themselves much more than either of them would with a Negro. Furthermore, each of them differs from the Mongolian and Chinese; less, however, than from the African and European.
Now, so far as this difference is concerned, the terms _typical_ and _sub-typical_, in their usual sense, are sufficient; the Mongolian being the _type_ of the variety which he represents, whilst the Malay and American each illustrate a _sub-typical_ modification.
But this is not all. In departing from one type, an individual, a tribe, or a nation may approach another. This is the case when the hair of the African becomes straight, his complexion brunette, and his lips thin. It is also the case when a Mongol becomes light-haired or blue-eyed. In each of these changes the effect is the same. The original conformation has become Europeanized. Hence we have--
1st. _Simple sub-typical deviation._--This occurs in the Eskimo. His face is broader than that of the Mongolian; but, as this increased breadth merely makes him somewhat unlike the natives of Central Asia, without approximating him to the African or European, the deviation is _simple_.
2nd. _Deviation with Transition._--The Finlander has a Mongoliform skull, but (very often) blue eyes and light hair; so that he agrees with the European where he differs with the Kalmuk. This is deviation and something more. It is deviation accompanied with the phenomenon of a transition in form.
Transitions in form, however, are of two kinds--_a._ those in which descent plays a part; _b._ those in which causes other than descent play a part.
_a._ The light-haired Finlander is probably one of three things--
1. The descendant of Mongolians passing into Europeans.
2. The descendant of Europeans passing into Mongolians.
3. The descendant of the common stock from which the Europeans on one side, and Mongolians on the other, originated. In all these cases his differential characters are accounted for by the doctrine of _descent_.
_b._ Contrast, however, the case of an Australian Black. He has Mongol characters and he has Negro characters; so that, looking to his _form_ only, he presents the phenomenon of transition; yet he is in none of the predicaments of the Finlander, since few ethnologists believe that, _in the way of descent_, he has any but the most indirect relationship to the African.