THE MARSUPIALS. 3C7 



sented by a small number of Cheiroptera and Rodents ; by some 

 Amphibia, Phocse, and Otidse (Seals and Bustards), which inhabit the 

 bays carved out of its long line of coast ; by the Marsupials and a 

 very limited order of Monotremata. The two latter groups are pre- 

 eminently characteristic of the Australian Fauna ; the second belongs 

 exclusively to it. Little, indeed, is wanting to make it identical with 

 the sub-class of the Marsupials, represented only in South America 

 by the genera Opossum didelphis, Hemiurus, and Chironectes, and 

 elsewhere limited to New Holland, Tasmania, New Guinea, New 

 Zealand, and some other less important islands of Oceania. 



The Marsupials (from the Greek ju.dp<rv7ro$, a purse) owe their 

 distinctive name to a very curious peculiarity in the organization of 

 the females. The latter bring their young into the world while still 

 very feeble, and of themselves fix them to their breasts, where they 

 remain attached until they have acquired that degree of development 

 which all other mammals possess at their birth. Generally the breasts 

 are covered with a loose skin, forming a sort of pouch or purse, in 

 which the young are concealed, which protects them against climatic 

 changes, and enables the mother conveniently to carry them every- 

 where about with her. Two particular bones, called the marsupial 

 bones, attached to the pubis, and placed amidst the abdominal muscles, 

 support this pouch. They assist, says Professor Owen, in producing 

 a compression of the mammary gland, necessary for the alimentation 

 of a peculiarly feeble offspring, and they defend the abdominal viscera 

 from the pressure of the young as they increase in size, during their 

 mammary or marsupial existence, and still more when they return to 

 the pouch for temporary shelter. 



The marsupials present, moreover, in the different families com- 

 posing the order, a great diversity of organization. Most of them 

 are herbivorous or frugivorous ; but there are some which prefer 

 animal nourishment, and which, in their habits as well as in the 

 structure of their jaws and their digestive apparatus, closely approach 

 the carnivora. 



The order of which I am speaking includes some animals of great 



