4 



CHORDATA. 191 



Sub-Class II. METATHERIA (Didelphia, 

 Implacentalia). 



Order 1. Marsupialia, pouched animals. Epipubic (marsupial) 

 bones ; in the female, two uteri, usually two vaginas and a marsupial 

 pouch, genital aperture and anus surrounded by a common sphincter ; 

 in the male, scrotum suspended in front of the penis. Auditory bulla 

 formed by alisphenoid, angle of the lower jaw inflected. Generally very 

 numerous teeth, which (with a few exceptions) are not changed ; incisors 



O Q 



never - -- . No allantoic placenta (so far as known). 

 3 3 



(a.) R a p a c i a, carnivorous marsupials. Perameles, 4 -r- 



3 13 



Myrmecobius, . Dasyurus viverrinus, dasyure. Thyla- 



o 1 4 5 



cinus, native wolf. Thylacoleo, Pleistocene. 



(6.) Pedimana, opossums. Dentition carnivorous, and resembling 



. Didelphys Americana, Ameri- 

 can opossum ; as many as twenty-seven young at a birth. Chironectes. 

 (c.) Carpophaga, frugivorous marsupials with corresponding den- 

 tition. Phalangista vulpina, phalanger. Petaurus. Phascolarctos, 



JL JL J_| 



1 114* 

 (d.) Poephaga (Macropoda), springing marsupials. The two lower 



incisors horizontal ; dentition LJ Microlestes from the 



1014 



Trias. Diprotodon australis in the Pleistocene. Macropus (Halma- 

 turus) gigantea, kangaroo. 



(e.) Glirina (Rhizophaga), gnawing marsupials. Phascolomys 



wombat 



that of the Insectivora, ____ 



