MAMMALIA. 



383 



tion. Immediately on the birth of the young one, the mother 

 took it up in her fore-paws, opened the pouch with them, and 

 deposited the young within. "In five minutes she was jump- 

 ing about tlie place as if nothing had happened." * 



Above one hundred and twenty species of Marsupial animals 

 have been recorded, forming about one-twelfth of the entire 

 number of mammalia. lu size thei'e is great diversity, ranging 

 from a diminutive Opossum, which is little larger than the 

 common Mouse, to the great Kangaroo t already mentioned; 

 and the disparity in size is still greater if we extend our view 

 to extinct species, as Professor Owen, from the fossil remains 

 of one brought from Austraha, is of opinion that the animal 

 must, when livmg, have been of bulk superior to that of the 

 Rhinoceros. 



Some Marsupial animals are so inferior in certain structural 

 peculiarities to the rest, and approach so much in these points 

 to birds and reptiles, that they form a distinct section bearing 

 a distinct name {Monolremata) .% To this division belong the 



Fig. 301.— Obmtbory.iccs. 



• Proceedings of the Zoological Society, 12th Nov., 1844. Letter from 

 the Rt. Hon. the Earl of Derby, President of the Society. In the instance 

 referred to, the period of Utero-gestation was under one month. 



t Didelphys pusilla. | Signifying one orifice or outlet. 



