MAKSri'IALS. 285 



of growth of the animals,* — the tipped or barbed tongue of the Opossum, — the resemblances to birds 

 of the allied Monotremes.^and the structure of the sternum and shoulder, both in the Echidna 

 and the Ornithorhj'nchus, which, although bearing a considerable resemblance to these parts in 

 birds, have a still greater coincidence with those of the Lizards and Ichthj'osauri. These facts 

 are all evidences of the Marsupials holding the lowest place in organisation in mammals, and 

 hence, presumablj^, the source, or one of the sources, from which the placental animals proceeded. 

 Although named from their bearing a marstqnion, or pouch, for the reception of their early born 

 young, they do not all possess either the marsupium itself or the marsupial bones which usually 

 accompany it. The Monotremes have it not, neither has the Myrmecobius, which is allied in 

 many respects to the Echidn.'e. Most of the Phascogales and Antechini are destitute of a pouch, 

 and one large section of the Opossums is also without it. In others, as Thylacinus, the pouch 

 is present, but the marsujjial bones are absent. 



Professor Owen has suggested the following ingenious exj)lanation of the teleological pm-poses 

 of this structure : — " I have always connected with the long droughts in Australia — with the 

 extensive tracts where there are no waters — with the difhculty of obtaining that necessary 

 element of life, the singular peculiarity of organization which prevails among the Mammalian 

 quadruijcds of Australia, viz. the possession of a soft, warm, well-lined, portable nursery pocket 

 or perambulator. Take the case of one of our wild qiuxdrupeds — suppose a fox or wild cat ; they 

 make their nest ; they have their litter. Suppose it should happen that they must travel one or 

 two hundred miles to get a drink of water, impelled by the peculiar thirsty condition of a 

 nursing mother, but obliged to leave the little family at home, where woidd that family be when 

 the parent returned from its hundred miles' journey — the poor little blind deserted litter ? Why! 

 starved to death. In order that quadrupeds should be fitted to exist in a great continent like 

 Australia, where the meteoric conditions are such as to produce the dilemma I have instanced, 

 those quadrupeds must possess an organization suited to such peculiar and climatal conditions. 

 And so it is. That form of mammalian quadruped in this great continent native to it, and born 

 so as to make their migrations to obtain that necessity of life, has the superadded pouch and 

 genetic peculiarities, enabling them to carry their young ones wherever they go. And since we 

 find that marsupial animals have lived in Australia from a very remote period, so may we infer 

 that its peculiar climate has prevailed during as vast a lapse of time." 



The fancy is ingenious, but wiU not bear much handling. The young litter would be still 

 better protected by remaining luiborn, as in the placental animals, until they are nearly ready 

 to care for themselves, instead of being prematurely disclosed and placed in the perambulator. 

 Besides this, purely desert animals are able to live without water. If such an apjDaratus 

 were necessary for desert animals, those inhabiting the Sahara have more need of it than those 

 in Australia. Moreover, although Australia is subject to periodical droughts, and in some parts 

 is desert, that is by no means its general character. Lastlj^, if it is a true explanation, it should 

 follow that the whole earth in the eocene and oolitic epoch was as dry and thirsty as Australia 

 now is ; a supjDosition inconsistent with the known luxuriance of the vegetation of these times. 



In examining into the distribution of the Marsupials we must remember that Australia has, in 



* Gould says, " I have observed tliis to occur with all Like the rogue Elephants of Ceylon, these patriarchs 



Slarsupials, but especially with Kangaroos. The great are often solitary, and are generally very savage." Gould's 



herds of the grey species, Macropds major, are frequently "Mammals of Australia, Introduction." 

 headed by an enormous male or boomer, as he is called. 



