372 REVIEWS—ON THE ORIGIN OF SPECIES. 
from a single variety, it seems evident that, in spite of the most judi- 
ciously-exercised selection in continuing the breed so as to produce 
the greatest possible variation, no great success could in this respect 
be arrived at; and a return to the characters of the original type 
would be constantly occurring. In the case of the dog, this is appar- 
ently allowed by Mr. Darwin, for, whilst expressing his conviction that 
all our domestic pigeon-breeds have descended from the rock pigeon, 
he does not regard our various dogs as the descendants of a single 
wild species. But granting that, in the case of the pigeon, and even 
in that of the dog, horse, &c., all known varieties have sprung from 
one existing or extinct type-pair—granting this—what does the ad- 
mission amount to? Simply to the fact, that certain species are capa- 
ble of great variation ; but, after all, of a variation amounting to no 
real specific, much less generic, difference. Stay! cry the upholders 
of this theory: a certain amount of time is required for the produc- 
tion, in this manner, of changes to that extent. We point to the 
monumental records of Egypt—but these, we are told, are but the 
works of yesterday. We exhume the dead forms of the geologic Past 
—and the assumed imperfection of our record is brought against us. 
On this latter point however, we shall have more to say in the sequel. 
In his succeeding chapter, the author discusses some important 
points connected with “variation under Nature; but much of his 
argument is here based rather on the deficiency of our present 
knowledge, than on absolutely-proved facts. He points out for in- 
stance, how greatly certain naturalists differ as to what should be con- 
sidered species and what varieties, in particular genera, more especially 
-amongst plants and insects ; but, rightly considered, although this may 
go far to prove the unnatural sub-divisions of the systematists, it can- 
not be looked upon as helping in any material way to explain the 
origin of true species : id est, of God’s actual creations as distinguished 
from the necessarily imperfect conceptions of man. The grand argu- 
ment of the chapter is founded on the (to a great extent, perhaps, un- 
doubted) fact, that, in large genera, the amount of difference between 
the included species is often exceedingly small; and that such species 
present also, as a general rule, more varieties than belong to the spe- 
cies of smaller genera. 
‘‘ From looking at species as only strongly-marked and well-defined varieties, I 
was led to anticipate that the species of the larger genera in each country would 
oftener present varieties than the species of the smaller genera; for wherever 
