Buller. — Illustrations of Darwinism. 81 



which used them least, were preserved ; till in process of time, 

 as we now see, the insects of Madeira have become wingless 

 and terrestrial, or, if they have not entirely lost their wings, 

 have had them so reduced as to be useless for flight. To my 

 mind it would net be right to confound these wingless insects 

 with the lower forms of the " more generalized ancestors," but 

 rather to assign them a place among the " higher and more 

 specialized groups." For it must be borne in mind that, as 

 Mr. Wallace himself expresses it (page 120), the "remarkable 

 advance in the higher and larger groups does not imply any 

 universal law of progress in organization, because we have afc 

 the same time numerous examples of the persistence of lowly- 

 organized forms, and also of absolute degradation or degenera- 

 tion. Serpents, for example, have been developed from some 

 lizard-like type which has lost its limbs ; and though this loss 

 has enabled them to occupy fresh places in nature, and to 

 increase and flourish to a marvellous extent, yet it must be 

 considered to be a retrogression rather than an advance in 

 organization. The same remark will apply to the Whale tribe 

 among mammals ; to the blind amphibia and insects of the 

 great caverns ; and among plants to the numerous cases in 

 which flowers, once specially adapted to be fertilized by 

 insects, have lost their gay corollas and their special adapta- 

 tions, and have become degraded into wind-fertilized forms." 

 But it seems to me that on this point Mr. Wallace is incon- 

 sistent with himself ; because at page 481, after referring to 

 my figure of the wing in vol. iii. of our "Transactions," he 

 says, " Even in the Apteryx, the minute external wing bears 

 a series of nearly twenty stiff quill-like feathers" ; and he goes 

 on to say, " These facts render it almost certain that the 

 Struthious birds do not owe their imperfect wings to a direct 

 evolution from a reptilian type, but to a retrograde develop- 

 ment from some low form of winged birds, analogous to that 

 which has produced the dodo and the solitaire from the 

 more pronounced pigeon-type." He adds that our best 

 anatomists agree that both Dinornis and Apteryx are more 

 nearly allied to the cassowaries and emus than to the 

 ostriches and rheas.* Now, from this point of view, I think 

 the language in which I long ago characterized the Kiwi — 

 although challenged by Professor Hutton and others — is fully 

 justified — namely, that it is the diminutive and degenerate 

 representative of the ancient colossal forms of wingless birds. 



* Afc page 416, op. cit., Mr. Wallace says, " Whales, like Moas and 

 Cassowaries, carry us back to a remote past, of whose conditions we know 

 too little for safe speculation. We are quite ignorant of the ancestral 

 forms of either of these groups, and are therefore without the materials 

 needful for determining the steps by which the change took place, or the 

 causes which brought it about." 

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