642 COLLEGE ZOOLOGY 



SUBCLASS I. PROTOTHERIA. EGG-LAYING MAMMALS. 



Order i. Monotremata. MONOTREMES. Examples: Or- 

 nithorhynchus, duckbill (Fig. 513); Echidna, spiny ant- 

 eater. 



SUBCLASS II. EUTHERIA. VIVIPAROUS MAMMALS. 

 Division I. DIDELPHIA (METATHERIA)'. MARSUPIALS. 



Order i. Marsupialia. MARSUPIALS. Mammals which 

 usually carry their young in a marsupium or pouch; 

 allantoic placenta usually absent. 

 Suborder i. POLYPROTODONTIA. CHIEFLY CARNIVO- 

 ROUS MARSUPIALS. Marsupials with eight or ten in- 

 cisors in the upper jaw, and at least three pairs in the 

 lower jaw. Examples: Didelphis, opossum (Fig. 514); 

 Thylacomys, rabbit bandicoot. 



Suborder 2. DIPROTODONTIA. MOSTLY HERBIVOROUS 

 MARSUPIALS. Marsupials with not more than three 

 pairs of incisors in the upper jaw, and usually one pair 

 of large incisors in the lower jaw. Examples: Cceno- 

 lesies, caenolestes; Phalanger, cuscus; Macro pus, kan- 

 garoo and wallaby (Fig. 515). 



Division II. MONODELPHIA (PLACENTALIA, EUTHERIA). - 

 EUTHERIA nourished before birth by a typical pla- 

 centa; young never carried in a pouch. 

 Section A. UNGUICULATA. CLAWED MAMMALS. 



Order i. Insectivora. INSECTIVORES. Small, usually 

 terrestrial, clawed mammals; feet plantigrade, generally 

 pentadactyle; molars enamelled, tuberculated, and 

 rooted. Examples: Erinaceus, hedgehog; Condylura, 

 star-nosed mole; Sorex, shrew (Fig. 516). 



Order 2. Dermoptera. DERMOPTERA. Two genera of 

 flying mammals resembling insectivores in the structure 

 of the skull and the canine teeth. They inhabit the 

 forests of Malaysia and Philippine Islands, and are 

 popularly called flying lemurs. 



Order 3 . Chiroptera. BATS. Clawed mammals with fore 



