POUCHED ANIMALS. 73 



covered with hair, open their eyes and are able to live on other 

 food than milk. For a long time after they have left this pouch, 

 they fly to it as a place of refuge when threatened by any danger. 

 (Plate 3, jig. 9.) In those species that have no pouch, but a 

 prehensile tail, the young are pendant from the belly of the 

 mother for a certain time; then they mount upon her back, and, 

 for the sake of support, wrap their tails around hers. 



3. All these animals which are so intimately linked to each 

 other by the manner in which their young are developed, differ 

 very much in other respects. In some, the dental system is pre- 

 cisely like that of the intectivora, and accordingly, they feed 

 upon similar food ; in others, that still possess the three sorts of 

 teeth, the molars are tuberculous in place of being studded with 

 points, and hence their frugivorous diet ; and there are some that 

 want the canine teeth, which, if we take this circumstance into 

 consideration, should be placed amongst the Rodentia, (Plate 3, 

 fig. 12 ) These animals also differ from each other in their 

 general form and habits. 



4. The Marsupialia have only been found in America, on some 

 of the islands of the South Sea, and particularly in New Holland, 

 which, with some exceptions, contains only mammiferous animals 

 of this order. 



5. The order of Marsupialia is divided into six tribes, as follows : 



First Tribe. Two long canines in each jaw; several small incisors; molars 

 studded with points. (Opossum.) 



Second Tribe. The superior canines long and pointed, but the inferior 

 rudimentary, or entirely wanting; six small incteors above, but only 

 two large ones below. Thumb large and directed backwards ; the 

 two next fingers joined as far as the nails (Phalangers.) 



Third Tribe. Two large incisors above with some small ones adjoining, and 

 two small canines; no thumb behind; paws very short. (Koala.) 



Fourth Tribe. Dental system nearly the same as in the preceding tribe; 

 no thumb on the posterior extremeties which, as well as the tail, are 

 very long. (Potoroos.) 



Fifth Tribe. Without canines ; a long vacant space between the incisors 

 and molars; several incisors in the upper jaw; posterior extremities 

 and tail very long. (Kangaroos.) 



Sixth Tribe. No canines; two long, inclosed incisors in each jaw; molars 

 studded with transverse ridges ; tail short. (Phascolomys.) 



3. Are all Marsupials alike? What is the nature of their diet ? Is the 

 dental system the same in all Marsupials? 



4. In what parts of the world ar^ the Marsupi ih found/ 



5. How is the order of Marsupialia divided? What are the characters 

 which distinguish the Opossum from other Marsupials? What are the or- 

 ganic characters of the Phalangers ? By what features can the Koala be 

 recognised ? What are the characters of the Potoroos ? What are the or 

 ganic characters of the Kangaroo ? 



