Origin of Species Variorum

→ to existing species in 1869 1872

in 1859 1860 1861 1866

→ will of course 1869

will always 1859 1860 1861 1866

would of course 1872

→ dog, 1859 1860 1861 1866 1869

case of the dog, 1872

→ in this latter respect must 1869 1872

must 1859 1860 1861 1866

→ quickly enough. 1859 1860 1861 1866 1869

still more quickly. 1872

→ sometimes 1859 1860 1861 1866 1869

easily err in 1872

by successive slight modifications, each better and

better,

better

for

fitted, for

so trifling an object as

driving

to drive

away flies; yet we should pause before being too positive even in this case, for we know that the distribution and existence of cattle and other animals in South America absolutely

depends

depend

on their power of resisting the attacks of insects: so that individuals which could by any means defend themselves from these small enemies, would be able to range into new pastures and thus gain a great advantage. It is not that the larger quadrupeds are actually destroyed (except in some rare cases) by

the

....

flies, but they are incessantly harassed and their strength reduced, so that they are more subject to disease, or not so well enabled in a coming dearth to search for food, or to escape from beasts of prey.

Organs now of trifling importance have probably in some cases been of high importance to an early progenitor, and, after having been slowly perfected at a former period, have been transmitted →to existing species in nearly the same state, although now

become

....

of very slight use;

and

but

any actually injurious deviations in their structure →will of course have been checked by natural selection. Seeing how important an organ of locomotion the tail is in most aquatic animals, its general presence and use for many purposes in so many land animals, which in their lungs or modified swimbladders betray their aquatic origin, may perhaps be thus accounted for. A well-developed tail having been formed in an aquatic animal, it might subsequently come to be worked in for all sorts of

purposes,—

purposes,

as a fly-flapper, an organ of prehension, or as an aid in turning, as

with

the →dog, though the aid →in this latter respect must be slight, for the hare, with hardly any tail, can double →quickly enough.

In the second place, we may →sometimes

attribute

attributing

wrongly attribute