CHIEF DIVISIONS OF THE ANIMAL KINGDOM. 89 



CLASS V. MAMMALIA (Mammals or Quadrupeds). Respiratory organs 

 in the form of lungs, which are never connected with air-sacs placed in 

 different parts of the body. Heart four-chambered. Blood warm. Skull 

 united to the backbone by two articulating surfaces or " condyles." Each 

 half of the lower jaw composed of a single piece. Appendages of the skin 

 in the form of hairs. Young nourished by means of a special fluid the 

 milk, secreted by special glands the mammary glands. Animal vivi- 

 parous. 



A. NON-PLACENTAL MAMMALS. The young not provided with a 

 placenta. 



Order 1. Monotremata. Ex. Duck-mole (Ornithorhynchus), Spiny 

 Ant-eater (Echidna). 



Order 2. Marsupialia. Ex. Kangaroos (Macropodidee), Kangaroo- 

 bear (Phascolarctos), Phalangers (Phalangistidse), Op- 

 ossums (Didelphidae), Tasmanian Devil (Dasyurus). 



B. PLACEXTAL MAMMALS. The young provided with a placenta. 



Order 3. Edentata. Ex. Sloths (Brady podidae), Armadillos (Dasy- 

 podidae), Hairy Ant-eaters (Myrmecophagidae), Scaly 

 Ant-eaters (Manis). 



Order 4. Sirenia. Ex. Manatee (Manatus), Dugong (Halicore). 



Order 5. Cetacea. Ex. Whalebone-whales (Balaenidae), Sperm- 

 whales (Physeteridae), Dolphins and Porpoises (Del- 

 phinidae). 



Order 6. Ungulata (Hoofed Quadrupeds). Ex. Rhinoceros ; Tapir; 

 Horse, Ass, and Zebra (Equidae) ; Hippopotamus ; 

 Hogs and Peccaries (Suida) ; Camels and Llamas 

 (Camelidae) ; Giraffe ; Stags, Elk, Reindeer (Cer- 

 vidse) ; Antelopes (Antilopidse) ; Sheep and Goats 

 (Ovidse) ; Oxen and Buffaloes (Bovidae). 



Order 7. Dinocerata (extinct). Ex. Dinoceras. 



Order 8. Tillodontia (extinct). Ex. Tillotherium. 



Order 9. Toxodontia (extinct). Ex. Toxodon. 



Order 10. Hyracoidea. Ex. Hyrax. 



Order 11. Proboscidea. Ex. Elephants (Elephas). 



Order 12. Carnivora. Ex. Seals (Phocidae), Bears (Ursidae), Ra- 

 coons (Procyon), Badgers (Melidae), Weasels and 

 Otters (Mustelidae), Civets and Genettes (Viver- 

 ridae), Dogs, Wolves, and Foxes (Canidae) ; Hyaenas 

 (Hyaenidae), Cats, Lynxes, Leopards, Tigers, Lions 

 (Felidse). 



Order 13. Rodentia. Ex. Hares and Rabbits (Leporidae), Porcu- 

 pines (Hystricidae), Beavers (Castoridae), Mice and 

 Rats (Muridae), Dormice (Myoxidae), Squirrels and 

 Marmots (Sciuridae). 



Order 14. Cheiroptera. Ex. Common Bats (Vespertilionidae), 

 Horseshoe-bats (Rhinolophidae), Vampire-bats (Phyl- 

 lostomidae), Fox-bats (Pteropidae). 



