232 MORPHOLOGY [Chap. XIV. 



whole subject is included under the general term of 

 Morphology. This is one of the most interesting de- 

 partments of natural history, and may almost be said to 

 be its very soul. What can be more curious than that 

 the hand of a man, formed for grasping, that of a mole 

 for digging, the leg of the horse, the paddle of the por- 

 poise, and the wing of the bat, should all be constructed 

 on the same pattern, and "shi)TiM iiTcliide similar bones, 

 in the "same reiatire" positions ? How curious it is, to 

 give a subordinate though striking instance, that the 

 hind-feet of the kangaroo, which are so well fitted for 

 bounding over the open plains, — those of the climbing, 

 leaf-eating koala, equally well fitted for grasping the 

 branches of trees, — those of the ground-dwelling, insect 

 or root eating, bandicoots, — and those of scfme other 

 Australian marsupials, — should all be constructed on 

 the same extraordinary type, namely with the bones of 

 the second and third digits extremely slender and 

 enveloped within the same skin, so that they appear like 

 a single toe furnished with two claws. Notwithstand- 

 ing this similarity of pattern, it is obvious that the 

 hind feet of these several animals are used for as widely 

 different purposes as it is possible to conceive. The 

 case is rendered all the more striking by the American 

 opossums, which follow nearly the same habits of life as 

 some of their Australian relatives, having feet con- 

 structed on the ordinary plan. Professor Flower, from 

 whom these statements are taken, remarks in conclusion : 

 " We may call this conformity to type, without getting 

 much nearer to an explanation of the phenomenon ; " 

 and he then adds " but is it not powerfully suggestive 

 of true relationship, of inheritance from a common 

 ancestor ? " 



