232 MORPHOLOGY. [Chap. XIV. 



subject is included under the general term of Morphol- 

 ogy. This is one of the most interesting departments 

 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 dig- 

 ging, the leg of the horse, the paddle of the porpoise, 

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

 same pattern, and should include similar bones, in the 

 same relative 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 eat- 

 ing, bandicoots, — and those of some other Australian 

 marsupials, — should all be constructed on the same ex- 

 traordinary 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 fur- 

 nished with two claws. Notwithstanding this similar- 

 ity of pattern, it is obvious that the hind feet of these 

 several animals are used for as widely difEerent pur- 

 poses as it is possible to conceive. The case is ren- 

 dered all the more striking by the American opossums, 

 which follow nearly the same habits of life as some of 

 their Australian relatives, having feet constructed 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 an- 

 cestor? " 



