KNOWLEDGE BY INVESTIGATION. 249 



Smuggling dogs distinguish custom-house officers ( c Percy 

 Anecdotes'). Certain London railway dogs recognise their 

 own special friends among the porters or other officers at the 

 different stations, making, it is asserted, no mistakes. Other 

 dogs frequently distinguish from among other men the mur- 

 derer, burglar, or thief; the butcher or dog-stealer ; the poor 

 beggar or tramp, their master's inferior, and the well-con- 

 ditioned visitor, their master's equal ; policemen or firemen, 

 with their calling and its object. Pet dogs occasionally dis- 

 cover their masters' bodies on a battle-field. 



The horse and the mule distinguish the semi-nude red 

 native Indian from the clothed, civilised white man on the 

 North American prairies, showing fear or suspicion in the 

 one case, confidence or unconcern in the other. The horse dis- 

 tinguishes its own master and rider from its master's domestics 

 and from crowds of other persons who are strangers to it. 

 Elephants recognise friendly soldiers on the field of battle 

 (Pierquin). The orang discriminates between native boys 

 and monkeys, and shows its pride by refusing to associate 

 with the latter (Cassell). 



It is somewhat singular that many animals, which readily 

 recognise persons, do not notice and remember with equal 

 readiness places, or vice versa. Thus the parrot shows a 

 decided power of recognising persons, and pigeons locality, 

 but not vice versa (Darwin) . 



Many animals, again, recognise each other as fully and 

 easily as certain dogs know their masters or mistresses. 

 And this kind of recognition of comrades or kinsmen 

 extends downwards in the zoological scale at least as low as 

 insects. Ants and bees, while caressing their acquaintances, 

 deal summarily with strangers, intruders, interlopers of 

 all kinds. Ants recognise their friends or fellows after 

 absence (Darwin and Lubbock), and they distinguish friends 

 from foes (Westwood). Sentinel bees know strangers, 

 enemies, or intruders, and deal with them according to 

 their character ; they also know the person of their queen 

 (Figuier). 



The recognition of things and the appreciation of their 

 significance are quite as common as the recognition of 



