Chap. VI. 
AFFINITIES AND GENEALOGY. 
195 
perhaps claim a distinct Sub-order or Family. Prof. 
Huxley, in his last work , 10 divides the Primates into 
three Sub-orders ; namely, the Anthropidse with man 
alone, the Simiadge including monkeys of all kinds, and 
the Lemuridge with the diversified genera of lemurs. As 
far as differences in certain important points of structure 
are concerned, man may no doubt rightly claim the 
rank of a Sub-order ; and this rank is too low, if we look 
chiefly to his mental faculties. Nevertheless, under a 
genealogical point of view it appears that this rank is 
too high, and that man ought to form merely a Family, 
or possibly even only a Sub-family. If we imagine 
three lines of descent proceeding from a common source, 
it is quite conceivable that two of them might after 
the lapse of ages be so slightly changed as still to 
remain as species of the same genus ; whilst the third 
line might become so greatly modified as to deserve 
“to rank as a distinct Sub-family, Family, or even 
Order. But in this case it is almost certain that 
the third line would still retain through inheritance 
numerous small points of resemblance with the other 
Two lines. Here then would occur the difficulty, at 
present insoluble, how much w T eight we ought to assign 
in our classifications to strongly-marked differences in 
some few points, — that is to the amount of modification 
undergone ; and how much to close resemblance in 
numerous unimportant points, as indicating the lines of 
descent or genealogy. The former alternative is the 
most obvious, and perhaps the safest, though the latter 
appears the most correct as giving a truly natural 
classification. 
To form a judgment on this head, with reference 
to man we must glance at the classification of the 
10 ‘ An Introduction to the Classification of Animals/ 1869, p. 99. 
O 2 
