236 INITIATIVE IN EVOLUTION 



written at great length in one small and the three other great orders 

 of Bats, Carnivores, Ungulates, and Rodents. As it has been 

 pointed out, Carnivores took to attacking larger prey, including 

 their less fortunate relatives, and stepped into the arena as carni- 

 vorous animals ; the Ungulates-to-be became herbivorous and deve- 

 loped into two great groups of hoofed animals, relying mainly on 

 flight for safety ; Rodents took to burrows for defence, ceased to 

 trouble much about attack, and became gnawing animals ; Bats 

 adopted an aerial life — a poor form of it indeed like that of the 

 aeroplane — and acquired a degraded fore-limb. Before leaving 

 these great orders of animals, whom I do not desire to compare 

 unfavourably with poor Louis, Jerome, Joseph or Lucien Bonaparte, 

 it is convenient here to refer to a fact which comes to light imme- 

 diately one looks into such a piece of classification as this of the 

 orders arising out of the loins of the early Insectivores, and that is 

 the functional conception underlying it. Doubtless pure functional 

 " characters " could never supply a whole system of classification 

 in the light of the modern doctrine of descent with modification, 

 and of zoological affinities. This is shown in a change from division 

 of six orders of Birds — Running, Swimming, Wading, Climbing, 

 Predatory and Perching Birds, to that of a few old-fashioned 

 Ratite Birds, and all the rest, one which seems the best that can be 

 offered at present. 



Insects, Mollusca, Birds. 



The grouping of animals by structural characters, and by 

 affinities which are assumed, though based on almost undeniable 

 evidence, whether into species, families, classes, phyla or sub-phyla, 

 has its apotheosis in Mollusca and Insects . As to the second of these 

 immense groups it has always seemed strange that their colourings 

 and structural characters should have ieceived such intensive study 

 from Weismann to the exclusion of Mollusca, when he set out to 

 prove his stupendous negative, and still more that of Vertebrates, 

 among which his chief difficulty and desired triumph would seem 

 to have lain. Mollusca though invertebrate are held by many to be 

 in the line of ancestry of the highest forms of life, and at any rate 

 insects are not. They are most fruitful fields indeed in which 

 Nature has been able to show what she could do by her stern 

 selective powers, but, from the point of view of descent with 

 modification, may be fairly compared to a review of an army in time 

 of peace, or the Kriegspiel of a German military staff. He who 

 concerns himself with the fundamental difficulties of the problems 

 at issue in evolution must make his notes of what experts tell him 



