THE TRAVELLING ORGANS OF ANIMALS 219 



land. The same is true of the Umbs and small feet of the ostrich. In the ostrich the digits of each foot are 

 reduced to t'.vo ; one digit being mainly employed in rurming. 



Five-toed typical mammals, with heavy, powerful frames, are not so well adapted for running on hard 

 surfaces as the horses, but they still exist — as witness the elephant. There was no necessity to manufacture the 

 horse from a five-toed mammal. The modified hmbs and sohd hoofs of the horse are rather to be regarded as a 

 proof of type and of adaptation and design, and, as such, are to be placed in the same category as the swimming 

 tail of the fish and reptile ; the swimming feet of the frog, beaver, ornithorhynchus, bird, seal, and walrus ; and 

 the flying wings of the insect, bird, and bat. These are all examples of structures adapted to the media the animals 

 are to traverse (Plates 1., li., and lii.). They are special creations rather than mere modifications. Environment 

 and externahties cannot produce them : they are constructed in young animals during development and before 

 they are required. They are means to ends, but do not prove consanguinity and descent. 



The rehabilitation of so-called missing links, and the modifications of existing structures, especially limb 

 structures, do not afford a safe basis for constructing a chart of consanguinity and descent. The presence of teeth 

 in the heads of a few extinct birds, the pattern of the teeth of the horse, and the decrease or increase in size, and 

 the appearance or disappearance of certain limb bones in the same or other individuals, do not prove evolution, 

 descent, or blood relationship. All these phenomena can be explained outside evolution and descent by reference 

 to the requirements of hfe and the exigencies of locomotion. That a few extinct birds had teeth does not prove 

 the descent of the bird from the reptile ; neither do the suppression of certain limb bones and the greatly increased 

 size of others give a vahd clue to the descent of the horse. 



As a matter of fact, the changes and modifications introduced into the animal series, because of modifications 

 in their organs of locomotion, are much greater than the data usually relied on for proving the doctrines of evolu- 

 tion and descent. I have, therefore, to express my conviction that evolutionists are not on safe ground when they 

 confine proofs of their views to one or two Unes of demonstration ; these being by no means the most obvious or 

 convincing. 



Professor Huxley regards America as the original home of the horse, rather than Europe, and mentions inci- 

 dentally that the animal died out on the American continent and had to be re-introduced. If this view be correct, 

 it is difficult to understand how such a contingency could have arisen, considering the vast extent and the resources 

 of the continent occupied. The dying out view is essentially opposed to the theory of environment. 



The evolution of the foot of the horse from a five-toed mammal is on a level with the evolution of the wing 

 of the pterodactyl, bird, and bat, from some five-fingered unknown flying ancestor. The wing of the bat (Fig. 38) 

 is composed of an arm, fore arm, wrist and five digits, with an outstretched membrane. The digits are nearly 

 of the same length, and take an equal share in supporting the membrane, and in the function of flight. In the 

 hand and phalanges of the pterodactyl (Fig. 37), as in the foot and phalanges of the horse, several of the digits 

 are dwarfed, one of them (the fourth) being enormously developed, and forming the chief organ of locomotion. Cer- 

 tain of the digits are dwarfed and rudimentary, but no one would, on this account, say that the ancient ptero- 

 dactyl was evolved from some extinct animal resembling the modern bat, which is a more highly differentiated 

 animal. Similar remarks are to be made of the wing of the bird. The wing of the bird is composed of a humerus 

 (arm bone), a radius and ulna (fore arm bones), modified carpal or wrist bones, and several digits or finger bones 

 run together and fused (Fig. 4:2). The arm and fore arm bones are independent and separate as in the primates 

 and in ourselves. The wrist and finger bones, on the contrary, are modified almost beyond recognition ; certain 

 of them being suppressed, while others are fused and sohdified to form one strong compound bone, which bears 

 the great primary feathers, the most essential structures in flight. The very remarkable modifications occurring 

 in the wing of the bird are quite as extraordinary as those occurring in the limb of the horse, but no one would 

 be so rash as to suppose that the bird, because of certain modifications in its wing, was descended from any form 

 of mammal, with distinct wrist bones and five distinct digits. Neither would the bat (a mammal, with five digits 

 in its wing) furnish the ancestor of the pterodactyl (Fig. 37). The dropping of certain bones, and the enlarging and 

 fusing of others, in the hmbs and travelhng organs of animals afford no proof of evolution in the strict or proper 

 sense. Evolution involves differentiation and increase in the number of parts. It is opposed to devolution, or the 

 decrease and suppression of parts. The increase and decrease of parts here referred to, which occur even in 

 the embryo, while inimical to the doctrine of evolution, supply strong arguments in favour of type, a First Cause, 

 design, and adaptation to given ends. 



The modifications required for locomotion can be traced in all animals, however diverse. They are not confined 

 to alHed animals, and consequently, and strictly speaking, have nothing to do with evolution ; evolution requiring 

 connecting hnks, and points of resemblance and continuity, in the evolving forms. 



The connecting hnks in locomotion do not support the theory of evolution'. Thus the galeopithecus or flying 



