On this passage Mr. Wallace remarks that the last five words "clearly show that such characters are usually not 'specific,' in the sense that they are such as distinguish species from one another, but are found in numerous allied species." But I cannot see that the passage shows anything of the sort. What to my mind it does show is, (_a_) that Mr. Darwin repudiated Mr. Wallace's doctrine touching the _necessary_ utility of _all_ specific characters: (_b_) that he takes for granted the contrary doctrine touching the inutility of _some_ specific characters: (_c_) that without in this place alluding to the proportional number of useless specific characters, he refers their origin in some cases to "the nature of the organism" (i.e. "spontaneous variability" due to internal causes), and in other cases to "the conditions" (i.e. variability induced by external causes): (_d_) that when established as a specific character by heredity, such a useless character was held by him not to tend to become obsolete by the influence of natural selection or any other cause; but, on the contrary, to be "transmitted in nearly the same state to numerous, otherwise modified, descendants"--or progeny of the species in genera, families, &c.: (_e_) and, therefore, that useless characters which are now distinctive of genera, families, &c., were held by him frequently, if not usually, to point to uselessness of origin, when first they arose as merely specific characters. Even the meaning which Mr. Wallace reads into this passage must imply every one of these points; and therefore I do not see that he gains much by apparently seeking to add this further meaning--viz. that in Darwin's opinion there must have been some unassignable reason preventing the occurrence of useless specific characters in cases where species are _not_ destined to become the parents of genera.