IN THE VERTEBRATA. 79 



In such comparisons, in short, we must distinguish be- 

 tween high capacity and high development. There fre- 

 quently is undeveloped or non-utilised capacity, though there 

 cannot be development without capacity. Even in the dog, 

 and still more in the Quadrumana, there is a moral potenti- 

 ality or capacity yet remaining to be developed by man when 

 he realises the importance, and the probable productiveness, 

 of moral education in the lower animals. 



The mental scale the scale of intelligence, of moral 

 development is, so far as our present data enable us to 

 judge, not quite synonymous with the zoological scale. The 

 most intelligent or moral animals are not necessarily those 

 nearest to man in the systems of classification commonly 

 adopted by zoologists. Neither as regards the six sub- 

 kingdoms of the animal kingdom, nor the classes of each 

 subkingdom, nor the orders of each class, nor the sub- 

 divisions of each order, nor the genera of each order or sub- 

 division, nor the species of each genus, can there be said to 

 be any unbroken line of continuity of psychical development. 

 In each subkingdom, class, order, genus, and species we 

 find some one or more groups standing forth pre-eminently 

 distinguished for their mental endowments, just as occurs 

 in the races, breeds, and individuals of a species. The 

 ant among the Invertebrata, the dog among the Vertebrata, 

 appear to constitute remarkable breaks in, or exceptions 

 to, the line of continuous or regular psychical evolution. 

 But such breaks or exceptions may be much more apparent 

 than real ; and the progress of our knowledge in comparative 

 psychology will probably render them less and less promi- 

 nent. 



Even as regards man himself it must be borne in mind 

 that, as has been shown in other chapters, there are countless 

 thousands many whole races that are intellectually and 

 morally the inferiors of many well-trained Mammals, such as 

 the chimpanzee, orang, dog, elephant, or horse; or birds, 

 such as the parrot, starling, magpie, jackdaw, and various 

 crows ; as well as of many animals much lower in the 

 zoological scale, and that are not trained by man at all, such 

 as the ant, bee, and wasp. 



