XIX 



THE ORIGIN OF MAMMALS 



1 . Classification 



Class Reptilia 

 Subclass *Synapsida 

 Order i. *Pelycosauria (= Theromorpha). Carboniferous-Per- 

 mian. 

 * Varanosaurus ; *Edaphosaurus ; *Dimetrodon 

 Order 2. *Therapsida. Permian-Jurassic 

 Suborder i. *Dicynodontia 



*Gakpus; *Moschops; *Dicynodon; *Kannemeyeria 

 Suborder 2. *Theriodontia 



*Cy?iog?iathus; * Scymnognathns ; *Bauria; *Dromatherium; 

 *Tritylodon; *Oligokyphus 



Class Mammalia 

 Subclass 1. Eotheria 

 # Order Docodonta. Trias-Jurassic 



*Morganucodon, Trias, Europe; *Docodon, Jurassic, N. America 

 and Europe 

 Order inc. sed. *Diarthrognathus 



Subclass 2. Prototheria 

 Order Monotremata. Pleistocene-Recent. Australasia 



Tachyglossus ( = Echidna), spiny anteater, Australia; Zaglossus 

 (= Proechidna), New Guinea; Ornithorhytichus, platypus, 

 Australia 



^Subclass 3. Allotheria 

 *Order Multituberculata. Jurassic-Eocene. Europe and N. 

 America 

 *Plagiaulax, Jurassic, Europe; *Ptilodus, Palaeocene, N. 

 America 



Subclass 4. Theria 



*Infraclass 1. Pantotheria 



*Order 1. Eupantotheria. Jurassic. Europe and N. America 



*A mphitherium 

 *Order 2. Symmetrodonta. Jurassic. Europe and N. America 

 * Spalacotherium 



