CLASSIFICATION OF MAMMALS. 629 



Subclass II. Didt'lphia. Order Marsitpialia. Mammals with a mar- 

 supium and bones supporting it. (Macropus, Didelphys.) 



Subclass III. Monodephia. Placental mammals. 



Super-order I. Ineducabilia. Brain with a relatively small, 

 smooth cerebrum. 



Order 1. Bruta. Incisors absent; sometimes toothless. 

 (Bradypus.) 



Order 2. Glires. Rodents, incisors large. (Sciurus.) 



Order 3. Insectivora. Fore limbs often peculiarly adapted 

 for burrowing ; molars with conical cusps. (Scalops.) 



Order 4. Chiroptera. Fore limbs adapted for flight. (Ves- 

 pertilio.) 



Super-order II. Edvcabilia.- Brain with a relatively large, con- 

 voluted cerebrum. 



Order 5. Cet\ Cetaceans; fish-like in form, no hind 

 limbs. ^Balaena.) 



Order 6. Sirenia. FisTi-like in form, but wit'fi ascending 

 rami to the lower jaw ; teeth ruminant-like. (Mana- 

 tus.) 



Order 7. Proboscidea. Snout prolonged into a proboscis. 

 (Elephas.) 



Order 8. Hyracoidea. Long curved incisors ; feet with 

 pads; toes encased in hoofs. (Hyrax.) 



Order 9. Toxodontia. Extinct forms, with well developed 

 incisors. (Toxodon.) 



Order 10. Ungulata. Ungulates ; toes encased in hoofs. 

 (Equus, Bos.) 



Order 11. Carniwra. Teeth pointed; claws large. (Felis, 

 Canis.) 



Order 12. Primates. Brain with cerebrum nearly or quite 

 covering the cerebellum ; nails usually present ; body 

 quadrupedal, quadrumanous, or erect and bimanous. 

 (Cebus, Gorilla, Homo.) 



Laboratory Work. All the craniate vertebrates may be dissected in 

 the same general manner, either under water in pans, or, if large, upon 

 the dissecting table. The necessary tools are a scalpel, forceps, scis- 

 sors, and tenaculum or hook for suspending the specimens or portions 



