so candid and careful as the author of the theory in question, will feel obliged, rather than the reverse, by the suggestion of all the doubts and difficulties which can be brought against it.

What is to be brought forward may be summed up as follows:

That "Natural Selection" is incompetent to account for the incipient stages of useful structures.

That it does not harmonize with the coexistence of closely-similar structures of diverse origin.

That there are grounds for thinking that specific differences may be developed suddenly instead of gradually. That the opinion that species have definite though very different limits to their variability is still tenable.

That certain fossil transitional forms are absent, which might have been expected to be present.

That some facts of geographical distribution supplement other difficulties.

That the objection drawn from the physiological difference between " species" and races still exists unre

futed.

That there are many remarkable phenomena in organic forms upon which "Natural Selection" throws no light whatever, but the explanations of which, if they could be attained, might throw light upon specific origination.

Besides these objections to the sufficiency of "Natural Selection," others may be brought against the hypothesis of "Pangenesis,” which, professing as it does to explain great difficulties, seems to do so by presenting others not less great-almost to be the explanation of obscurum per obscurius.

THE

INCOMPETENCY

CHAPTER II.

66

OF NATURAL SELECTION TO ACCOUNT FOR THE INCIPIENT STAGES OF USEFUL STRUCTURES.

Mr. Darwin supposes that Natural Selection acts by Slight Variations.-These must be useful at once.-Difficulties as to the Giraffe; as to Mimicry; as to the Heads of Flat-fishes; as to the Origin and Constancy of the Vertebrate Limbs; as to Whalebone; as to the Young Kangaroo; as to Sea-urchins; as to certain Processes of Metamorphosis; as to the Mammary-gland; as to certain Ape Characters; as to the Rattlesnake and Cobra; as to the Process of Formation of the Eye and Ear, as to the Fully-developed Condition of the Eye and Ear; as to the Voice; as to Shellfish; as to Orchids; as to Ants.-the Necessity for the Simultaneous Modification of Many Individuals.-Summary and Conclusion.

"NATURAL Selection," simply and by itself, is potent to explain the maintenance or the further extension and development of favorable variations, which are at once sufficiently considerable to be useful from the first to the individual possessing them. But Natural Selection utterly fails to account for the conservation and development of the minute and rudimentary beginnings, the slight and infinitesimal commencements of structures, however useful those structures may afterward become.

1

Now, it is distinctly enunciated by Mr. Darwin, that the spontaneous variations upon which his theory depends are individually slight, minute, and insensible. He says, "Slight individual differences, however, suffice for the work, and are probably the sole differences which are effective in the production of new species." And again, after

1 "Animals and Plants under Domestication," vol. ii., p 192

2

mentioning the frequent sudden appearances of domestic varieties, he speaks of "the false belief as to the similarity of natural species in this respect." In his work on the "Origin of Species," he also observes, "Natural Selection acts only by the preservation and accumulation of small inherited modifications." And "Natural Selection, if it be a true principle, will banish the belief. . . of any great and sudden modification in their structure." Finally, he adds, "If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down."

Now the conservation of minute variations in many instances is, of course, plain and intelligible enough; such e. g., as those which tend to promote the destructive faculties of beasts of prey on the one hand, or to facilitate the flight or concealment of the animals pursued on the other; provided always that these minute beginnings are of such a kind as really to have a certain efficiency, however small, in favor of the conservation of the individual possessing them; and also provided that no unfavorable peculiarity in any other direction accompanies and neutralizes, in the struggle for life, the minute favorable variation.

But some of the cases which have been brought forward, and which have met with very general acceptance, seem less satisfactory when carefully analyzed than they at first appear to be. Among these we may mention “the neck of the giraffe."

At first sight it would seem as though a better example in support of "Natural Selection" could hardly have been chosen. Let the fact of the occurrence of occasional severe droughts in the country which that animal has in2 "Animals and Plants under Domestication," vol. ii., p. 414. 3 Origin of Species," 5th edit., 1869, p. 110. 4 Ibid., p. 111.

5

Ibid., p. 227.

habited be granted. In that case, when the ground vegetation has been consumed, and the trees alone remain, it is plain that at such times only those individuals (of what we assume to be the nascent giraffe species) which were able to reach high up would be preserved, and would become the parents of the following generation, some individuals. of which would, of course, inherit that high-reaching power which alone preserved their parents. Only the high-reaching issue of these high-reaching individuals would again, cæteris paribus, be preserved at the next drought, and would again transmit to their offspring their still loftier stature; and so on, from period to period, through æons of time, all the individuals tending to revert to the ancient shorter type of body, being ruthlessly destroyed at the occurrence of each drought.

(1.) But against this it may be said, in the first place, that the argument proves too much; for, on this supposition, many species must have tended to undergo a similar modification, and we ought to have at least several forms, similar to the giraffe, developed from different Ungulata.* A careful observer of animal life, who has long resided in South Africa, explored the interior, and lived in the giraffe country, has assured the author that the giraffe has powers of locomotion and endurance fully equal to those possessed by any of the other Ungulata of that continent. It would seem, therefore, that some of these other Ungulates ought to have developed in a similar manner as to the neck, under pain of being starved, when the long neck of the giraffe was in its incipient stage.

To this criticism it has been objected that different kinds of animals are preserved, in the struggle for life, in very different ways, and even that "high reaching" may be at

6 The order Ungulata contains the hoofed beasts; that is, all oxen, deer, antelopes, sheep, goats, camels, hogs, the hippopotamus, the different kinds of rhinoceros, the tapirs, horses, asses, zebras, quaggas, etc.

tained in more modes than one—as, for example, by the trunk of the elephant. This is, indeed, true, but then none of the African Ungulata have, nor do they appear ever to have had, any proboscis whatsoever; nor have they acquired such a development as to allow them to rise on their hind-limbs and graze on trees in a kangaroo attitude, nor a power of climbing, nor, as far as known, any other modification tending to compensate for the comparative shortness of the neck. Again, it may perhaps be said that leaf-eating forms are exceptional, and that therefore the struggle to attain high branches would not affect many Ungulates. But surely, when these severe droughts necessary for the theory oceur, the ground vegetation is supposed to be exhausted; and, indeed, the giraffe is quite capable of feeding from off the ground. So that, in these cases, the other Ungulata must have taken to leaf-eating or have starved, and thus must have had any accidental long-necked varieties favored and preserved exactly as the long-necked varieties of the giraffe are supposed to have been favored and preserved.

The argument as to the different modes of preservation has been very well put by Mr. Wallace, in reply to the objection that "color, being dangerous, should not exist in Nature." This objection appears similar to mine; as I say that a giraffe neck, being needful, there should be many animals with it, while the objector noticed by Mr. Wallace says, "A dull color being needful, all animals should be so colored." And Mr. Wallace shows in reply how porcupines, tortoises, and mussels, very hard-coated bombadier beetles, stinging insects, and nauseous-tasted caterpillars, can afford to be brilliant by the various means of active defence or passive protection they possess, other than obscure colora

7 The elephants of Africa and India, with their extinct allies, consti. tute the order Proboscidea, and do not belong to the Ungulata. 8 See "Natural Selection," pp. 60-75.