REVIEWS—ON THE ORIGIN OF SPECIES. 379 
is farther from our intention—the arguments here, become painfully 
akin to those of the “ Vestiges.’ Take the following for example: 
“Seeing that a few members of such water-breathing classes as the Crustacea 
and Mollusea are adapted to live on the land, and seeing that we have flying birds 
and mammals, flying insects of the most diversified types, and formerly had 
flying reptiles, it is conceivable that flying fish, which now glide far through the 
air, slightly rising and turning by the aid of their fluttering fins, might have been 
modified into perfectly winged animals. If this had been effected, who would 
have ever imagined that in an early transitional state they had been inhabitants of 
the open ocean, and had vsed their incipient organs of flight exclusively, as far as 
we know, to escape being devoured by other fish ?” 
If the author had attempted to show that an imperfectly-flying 
fish might become gradually modified into a fish possessing more 
perfect powers of flight, the principle might perhaps be admitted, at 
least for the sake of discussion: but when ‘‘ perfectly winged animals ” 
are spoken of, especially in connexion with the context, the argument, 
if if mean anything, implies the possible transformation of a flying 
fish into a pterodactyle or some kind of flying reptile; and through 
this, or without its intervention, into a bird or a bat—a transforma- 
tion involving most assuredly, greater difficulties, than any examples 
of petty, subordinate modifications, such as the author’s tabular lists 
may exhibit, will help us to consider one of little weight. Turning 
now to the second of the grave difficulties referred to above, the 
formation of a complex organ, like the eye of a vertebrated animal, 
by the gradual modification of an inferior organ in a lower type, we 
may again let the author speak for himself: only warning the reader 
unfamiliar with geological discussions, that where Mr. Darwin speaks 
of our having to descend far beneath the lowest known fossiliferous 
stratum to discover the earliest stages by which the eye in the verte- 
brated class has been perfected, he assumes data altogether denied 
by the greater number of cur most eminent geologists. The lowest 
sedimentary rocks (containing it should be remarked many beds 
which retain all their sedimentary characters, and thus agree with 
higher and fossiliferous strata) are generally looked upon as truly azoic 
formations: as deposits accumulated before the dawn of life upon the 
globe. The first fish-remains, moreover, the earliest recognised 
examples of Vertebrata, do not occur at or near the actual base of 
the fossiliferous strata, but only at the extreme upper limit of the 
Silurian formation; and in all our earliest fishes the eye exhibits 
