ORDER IX. MARSUPIALIA. 53 



the Edentata for a similar reason. But so peculiar and re- 

 markable is the structure of these animals, and so singular 

 their mode of nourishing their young, that it will be far more 

 intelligible and interesting to the student of natural history, 

 to have them placed together, and described as belonging to 

 a single order. 



The most remarkable circumstance, with regard to the 

 Marsupial animals, is the premature birth of their young, and 

 the exceedingly unformed and imperfect state in which they 

 are brought into the world. They are incapable of motion, 

 and scarcely exhibit even the rudiments of limbs or other ex- 

 ternal organs. Their mouth is simply a round orifice, with- 

 out distinction of parts ; but by means of it, they attach them- 

 selves to the nipples of the mother, and there remain immovably 

 fixed, deriving their nourishment from them, and gradually 

 improving in shape and increasing in size, until they are 

 as completely formed as other animals are at the time of 

 their birth. So small in proportion are the young when first 

 born, that the Kangaroo, which, when full grown, is as large 

 is a sheep, and weighs one hundred and fifty pounds, is at / 4 

 its birth no more than an inch in length, and weighs only 

 twenty-one grains. 



Generally, the female is furnished with a duplicature of the 

 skin of the abdomen, which forms a kind of bag, covering the 

 nipples, in which it places its young, and preserves them du- 

 ring the period of helplessness. Frequently, indeed, even af- 

 ter they have acquired strength to leave this pouch, they re- 

 treat into it upon the approach of danger. Sometimes, in 

 place of the pouch, there is simply a fold of the skin. The 

 pouch is supported by means of two bones attached to those 

 of the pelvis, from which proceed muscles that open or con- 

 tract its mouth, like the opening of a purse. These bones 

 are found also in the male, and in those species which have 

 not the complete pouch; and are always an indication that 

 the animal belongs to this order. 



The Opossum is as large as a cat, and covered with a thick 

 f'.ir of a dingy cast. It hunts after birds and their eggs, and 

 is destructive to poultry. It is found in many parts of the 

 United States. When pursued and overtaken, it feigns it- 

 self dead, and will give no signs of life during the presence 

 of its assailant, although tortured to a great degree. Its 

 young, which are sometimes six or seven in number, are ex- 

 ceedingly minute; and, although blind and without limbs, 

 find their way, by a sort of instinct, to the nipples, and adhere 

 5* 



