CHAPTER II 



MAMMALS IN GENERAL ; AND THE OliJGIN OF 

 THE B'BJTISH MAMMALIA 



Mammal is the most convenient term in English to apply to 

 the members of the class Mammalia, the highest development 

 of living forms on the earth's surface. The word, of course, is 

 derived from the Latin mamma, a teat, and embodies the most 

 obvious distinction between this group and the other vertebrates, 

 because all the Mammalia nourish their young after birth by a 

 liquid developed in glands which are provided with a nipple or 

 teat.' It must be admitted that at present " mammal " is a 

 somewhat pedantic designation, and is certainly never used by 

 the rustic. But it is difficult to see what other term is to be 

 chosen in preference, if accuracy of speech is desired. "Animal" 

 applies not only to mammals, but to every other living creature 

 which is not a vegetable. " Quadruped " is equally foolish, 

 because reptiles (and in a sense birds) also possess four limbs 

 which are usually devoted to purposes of locomotion. The old 

 Anglo-Saxon word deor ^ (our English word " deer ") has 

 become restricted to a small group of ruminants, and no longer 

 means all the beasts. The English term which comes nearest 



1 Except in the group of the Monotremes, where the liquid of the 

 mammary glands exudes through pores and not through the channel of a 

 nipple. In all the Mammalia except the Monotremes the milk is a sebaceous 

 fluid, but in the case of the Monotremes it would seem to be developed from 

 the sweat. 



^ Akin to the German Thier, hatin /era, Greek fker. 



