158 Review of Darwin's Theory on the Origin of Species, 
s theory brings us the other way to the same result, In 
escendants 
of a common parent but of all the related species also, Afinit 
relationship, all the terms which naturalists use figuratively to 
express an underived, unexplained resemblance among species, 
have a literal meaning upon Darwin’s s stem, which they little 
suspected, namely, that of inheritance. © Varieties are the latest 
offshoots of the genealogical tree in “an unlineal” order; spe 
cies, those of an earlier date, but of no definite distinction; 
enera, more ancient species, and so on. The human races, 
upon this view likewise may or may not be species according to 
the notions of each naturalist as to what differences are specific: 
but, if not species already, those races that last long enough are 
sure to become so. It is only a question of time. : 
How well the simile of a genealogical tree illustrates the mai 
ideas of Darwin’s theory the following extract from the Sun 
hows. ‘ 
p24 5 
genera, species of distinet genera much less closely related, and ane ; 
related in different cegrees, forming sub-families, families, orders, S1 — 
classes, aud classes. The several subordinate groups in any clan, 0 
be ranked in a single file, but seem rather to be clustered round pa 
and these round other points, and so on in almost endless cycles. > 
the view that each species has been independently created, I can se” 
explanation of this great fact in the classification of all onganlé beng 
but, to the best of my judgment, it is explained through inne 
the complex action of natural selection, entailing extinction and 
