MONKEY KIND. 325 



shutting, at the will of the animal ; and this is 

 performed by means of several muscles, and two 

 bones, that are fitted for this purpose, and that 

 are peculiar to this animal only. These two 

 bones are placed before the os pubis, to which 

 they are joined at the base ; they are about two 

 inches long, and grow smaller and smaller to 

 their extremities. These support the muscles 

 that serve to open the bag, and give them a fix- 

 ture. To these muscles there are antagonists, 

 that serve, in the same manner, to shut the bag ; 

 and this they perform so exactly, that in the liv- 

 ing animal the opening can scarcely be discern- 

 ed, except when the sides are forcibly drawn 

 asunder. The inside of this bag is furnished 

 with glands, that exude a musky substance, 

 which communicates to the flesh of the animal, 

 and renders it unfit to be eaten. It is not to be 

 supposed that this is the place where the young 

 are conceived, as some have been led to imagine ; 

 for the opossum has another womb, like that of 

 the generality of animals, in which generation is 

 performed in the ordinary manner. The bag we 

 have been describing may rather be considered 

 as a supplemental womb. In the real womb, the 

 little animal is partly brought to perfection ; in 

 the ordinary one, it receives a kind of additional 

 incubation, and acquires, at last, strength enough 

 to follow the dam wherever she goes. We have 

 many reasons to suppose that the young of this 

 animal are all brought forth prematurely, or be- 

 fore they have acquired that degree of perfec- 

 tion which is common in other quadrupeds. 



