DIVERGENT EVOLUTION THROUGH SEGREGATION. Sok 
equalled 10, while the ‘‘ Ratio of increase for the cross unions” (which I 
call m) equaled 5. Turning now to Table vy, we can easily find the 
ratio in which the number of pure-breeds will stand to the half-breeds, 
if the conditions continue long; for in the column in which m equals 5 
and in the line marked c=, we find 2, which means that the half- 
breeds will equal the pure-breeds multiplied by 25, or by +4. 
SEGREGATE VIGOR AND SEGREGATE FECUNDITY BETWEEN HUMAN RACES. 
My attention has recently been called to the following facts relating 
to the Japanese and Aino races, who have for many centuries met un- 
der circumstances favorable for interfusion without any apparent effect 
of this kind. I quote from ‘Memoirs of the Literature College, Im- 
perial University of Japan,” No. 1: “The Language, Mythology, and 
Geographical Nomenclature of Japan viewed in the Light of Aino 
Studies,” by Basil Hall Chamberlain, p. 43: 
“With what logic, it may be urged, do you invite us to accept a 
great extension of the Aino race in early Japan, when it is a physiolog- 
ical fact, vouched for by so high an authority as Dr. Baelz, that there 
is little or no trace of Aino blood in the Japanese people? In reply to 
this some would perhaps quote such examples as New England, whence 
the Indians have vanished, leaving nought behind them but their place- 
names. In Japan, however, the circumstances are different from those 
of New England. There has undoubtedly been constant inter-marriage 
between the conquerors and the native race upon the Aino border. We 
can infer this from history. Those who have traveled in Yezo know it 
by personal experience to-day. Nevertheless, these inter-marriages 
may well consist with the absence of any trace of Aino blood in the 
population. As a matter of fact, the northern Japanese, in whose 
veins there should be most Aino blood, are no whit hairier than their 
compatriots in central and southern Japan. Anyone may convince 
himself of this by looking at the coolies (almost all Nambu or Tsugaru 
men) working in the Hakodate streets during the summer months, 
when little clothing is worn. But the paradox is only on the surface. 
The fact is that the half-castes die out—a fate which seems, in many 
quarters of the world, to follow the miscegenation of races of widely 
divergent physique. That this is the true explanation of the phenom- 
enon was suggested to the present writer’s mind by a consideration of 
the general absence of children in the half-bred Aino families of his ae- 
quaintanece. Thus, of four brothers in a certain village where he staid, 
three have died leaving widows without male children and with only 
one or two little girls between the three. The fourth has children of 
both sexes; but they suffer from affections of the chest and from rheu- 
matism. Mr. Batchelor, whose opportunities for observation have been 
unusually great, concurs in considering this explanation as sufficient 
as it is simple. There are scores of mixed marriages every year. There 
