“Now, let us suppose that the ancestors of these various animals were all destitute of the very special protection they at present possess, as on the Darwinian hypothesis we must do. Let it be also conceded that small deviations from the antecedent colouring or form would tend to make some of their ancestors escape destruction, by causing them more or less frequently to be passed over or mistaken by their persecutors. Yet the deviation must, as the event has shown, in each case, be in some definite direction, whether it be towards some other animal or plant, or towards some dead or inorganic matter. But as, according to Mr. Darwin’s theory, there is a constant tendency to indefinite variation, and as the minute incipient variations will be _in all directions_, they must tend to neutralise each other, and at first to form such unstable modifications, that it is difficult, if not impossible, to see how such indefinite modifications of insignificant beginnings can ever build up a sufficiently appreciable resemblance to a leaf, bamboo, or other object for “natural selection,” to seize upon and perpetuate. This difficulty is augmented when we consider—a point to be dwelt upon hereafter—how necessary it is that many individuals should be similarly modified simultaneously. This has been insisted on in an able article in the ‘North British Review’ for June 1867, p. 286, and the consideration of the article has occasioned Mr. Darwin” (“Origin of Species,” 5th ed., p. 104) “to make an important modification in his views” (“Genesis of Species,” p. 38). To this Mr. Darwin rejoins:— “But in all the foregoing cases the insects in their original state, no doubt, presented some rude and accidental resemblance to an object commonly found in the stations frequented by them. Nor is this improbable, considering the almost infinite number of surrounding objects, and the diversity of form and colour of the host of insects that exist” (“Natural Selection,” p. 182, ed. 1876). Mr. Mivart has just said: “It is difficult to see how such indefinite modifications of insignificant beginnings _can ever build up a sufficiently appreciable resemblance to a leaf_, _bamboo_, _or other object_, _for_ ‘_natural selection_’ _to work upon_.” The answer is, that “natural selection” did not begin to work _until_, _from unknown causes_, _an appreciable resemblance had nevertheless been presented_. I think the reader will agree with me that the development of the lowest life into a creature which bears even “a rude resemblance” to the objects commonly found in the station in which it is moving in its present differentiation, requires more explanation than is given by the word “accidental.”