236 THE GENESIS OF SPECIES. [CHAP. 



Again, it has been contended that instances of color, as 

 in some apes ; of beauty, as in some shell-fish ; and of util- 

 ity, as in many orchids, are examples of conditions which 

 are quite beyond the power of Natural Selection to origi- 

 nate and develop. 



Next, the peculiar mode of origin of the eye (by the 

 simultaneous and concurrent modification of distinct parts), 

 with the wonderful refinement of the human ear and voice, 

 has been insisted on ; as also, that the importance of all 

 these facts is intensified through the necessity (admitted 

 by Mr. Darwin) that many individuals should be similarly 

 and simultaneously modified in order that slightly favora- 

 ble variations may hold their own in the struggle for life, 

 against the overwhelming force and influence of mere 

 number. 



Again, we have considered, in the third chapter, the 

 great improbability that from minute variations in all di- 

 rections alone and unaided, save by the survival of the 

 fittest, closely-similar structures should independently arise ; 

 though, on a non-Darwinian evolutionary hypothesis, their 

 development might be expected a priori. We have seen, 

 however, that there are many instances of wonderfully 

 close similarity which are not due to genetic affinity ; the 

 most notable instance, perhaps, being that brought for- 

 ward by Mr. Murphy, namely, the appearance of the same 

 eye-structure in the vertebrate and molluscous sub-king- 

 doms. A curious resemblance, though less in degree, has 

 also been seen to exist between the auditory organs of 

 fishes and of Cephalopods. Remarkable similarities be- 

 tween certain placental and implacental mammals, between 

 the bird's-head processes of Polyzoa and the pedicellarias 

 ef Echinoderms, between Ichthyosauria and Cetacea, with 

 very many other similar coincidences, have also been 

 pointed out. 



Evidence has also been brought forward to show that 



