: 
La 
Review of Darwin’s Theory on the Origin of Species. 157 
the species themselves and produce the present diversity. Mr. 
Agassiz believes that they have not even aflected the geograph- 
ical range and the actual association of species, still less their 
forms; but that every adaptation of species to climate and of 
species to species is as aboriginal, and therefore as inexplicable, 
as are the organic forms themselves. 
Who shall decide between such extreme views so ably main- 
tained on either hand, and say how much of truth there may be 
ineach? The present reviewer has not the presumption to un- 
dertake such a task. Having no prepossession in favor of natu- 
which attends a rigorous adherence to the impersonal style. _ 
_ We have contrasted’ these two extremely divergent theories, 
in their broad statements. It must not be inferred that they 
v 
‘weeping away the ground of their objective existence in Na- 
ture. The orthodox conception of species is that of lineal de- 
he species, and a practical rule, whic 
ia Y inferred to be compatible with a common origin. 
( . the usual concurrence of the whole body of naturalists _ 
‘ing the same data before them) as to what forms are species 
attests the value of the rule, and also indicates some real found- 
n for it in nature. But if species were created in numberless 
Viduals over broad spaces of territory, these individuals are 
Gis tes only in idea, and species differ from varieties on the 
hand and from genera, tribes, &c. on the other only in de- 
the: and no obvious natural reason remains for fixing upon 
which that degree as specific, at least no natural standard, b 
: the Pinions of different naturalists may be correlated. 
