632 



CHAPTER XXX. 



MAMMALIA. 



THE highest boon conferred upon the lower animals, " Hea- 

 ven's last best gift," is parental affection. The cold-blooded 

 Ovipara, unable in any manner to assist in the maturation of 

 their offspring, were necessarily compelled to leave their eggs 

 to be hatched by the agency of external circumstances ; and their 

 progeny, even from the moment of their birth, were abandoned 

 to chance and to their own resources for a supply of nourish- 

 ment. In Birds, the duties and the pleasures inseparable from 

 the necessity of incubating their ova, and of providing nutriment for 

 their callow brood, are indeed manifested to an extent unparalleled 

 in the preceding orders of Vertebrata ; but it is to the Mammalia 

 alone, the most sagacious and intelligent of all the inhabitants 

 of this world, that the Creator has permitted the full enjoyment 

 of paternal and maternal love, has thrown the offspring absolutely 

 helpless and dependent upon a mother's care and solicitude, and 

 thus confers upon the parent the joys and comforts that a mother 

 only knows, the dearest, purest, sweetest, bestowed upon the 

 animal creation. 



(708.) The grand circumstance whereby the entire class of 

 beings generally designated under the name of QUADRUPEDS may 

 be distinguished from all other members of the animal kingdom 

 is, that the females of every species are furnished with mammary 

 glands, secerning organs appointed to supply a secretion called 

 milk, whereby the young are nourished from the moment of 

 their birth, until they have reached a sufficient age to enable 

 them to live upon such animal or vegetable substances as are 

 adapted to their maturer condition. The possession of these 

 lactiferous glands would indeed be in itself a sufficiently decisive 

 characteristic of the whole group ; and if to this we add that their 

 visceral cavity is separated into a thorax and abdomen by a mus- 

 cular diaphragm^ and that they breathe by means of lungs pre- 

 cisely similar to our own, we need not in this place dwell upon 

 any more minute definition of the Mammiferous Vertebrata. 



