644 BIOLOGY. 



cisors mostly wanting, and occasionally all the teeth ; claws 

 very large and curved Ornithorynchi, Ant-eaters, Arma- 

 dillos and Sloths. 



Fam. 5. Snail-like Thricozoa, Herbivorous Marsupials. 



Rodent teeth, usually with stunted proximal and 

 canine teeth, lateral teeth level ; toes mostly connate and 

 very unequal ; they live in the Old World upon roots, 

 grass, and fruit Wombat, Dasyure, Kangaroo, Opossum. 



Fam. 6. Kracken-Haarthiere, Carnivorous Marsupials. 



Mostly more than six incisors, triangular molars and 

 large canines ; live in the New World and in Australia, 

 eating worms, insects, eggs and flesh Vulpine Pha- 

 langer, Phascogale, Beutelratze. 



The abnormal structure of the sexual parts reminds us 

 of the same relation in the Snails and Kracken. 



Order 3. Lungen-, Fell-, RingeWder-Haartliiere 

 Raubmduse. 



3569. Molar teeth mostly quadriacuminate, with a 

 break in the series, canines and pointed incisors, or 

 rodent teeth with lateral incisors, five toes ; live upon 

 worms and insects. 



Fam. 7. Worm-Thricozoa, Moles. 



Claws, sharp incisors or rodent teeth, with lateral 

 incisors or false molars ; live exclusively under the earth, 

 and cast up the mould. 



Fam. 8. Crustaceous Thricozoa, Shrews. 



Paws, rodent teeth, with small lateral incisors and 

 canine teeth. Many burrow passages without throwing 

 up the soil. 



Fam. 9. Ptilotal Thricozoa, Bats. 



Alary membrane between the feet and anterior digits ; 

 pointed canine and incisor teeth. 



Order 4. Sarco- Thricozoa Ungulata. 



3570. Body large and heavy ; teeth stunted, molars 

 uniform, tolerably obtuse ; feet fin- or hoof-like ; mostly 

 udders, rarely mammae. 



Fam. 10. Ichthyoid Thricozoa, Wliales. 



Skin naked ; no hind feet ; two horizontal caudal fins ; 



