V. CLASS MAMMALIA, Linn^ 



Warm -blooded Amniota, Allantoidea with milk -glands. ' 

 Covered with hair. Quadrate transformed into the m- (am*<0 

 mandible articulating with the squamosal. Two 

 ;ipital condyles. Ilio-sacral connexion preacetabular. With 

 ruro-tarsal joint. 



1. Sub-CLASS PEOTOTHEEIA, Huxley 



Oviparous. With a cloaca. Without chorion. 



Temporary marsupium, without nipples. 



Coracoids complete and articulating with the sternum. 



With large " epipubic or marsupial " bones. 



Mandible with (at least vestigial) an inner inverted angle. 



1. Order Allotheria, Marsh. Molars multitubercular. 

 Small mammals from the Triassic to the Eocene epoch. 



— Tritylodon. Trias, S. Africa. 

 Bolodon. Jurassic, England. 

 Allodon. Jurassic, Wyoming. 

 Plagiaulax. Jurassic, England. 

 Microlestes. Ehaetic, Europe. 

 Polymastodon. Eocene, New Mexico. 



2. Order Monotremata, Geoffroy = Ornithodelphia, de 

 Jlainville. Multi-tubercular molars are superseded by horny 



2overings of the jaws. Australian region. 

 Ornithorhynchus in Australia. 



Echidna and Proechidna. Australia and New Guinea ; 

 since the Plistocene of Australia. 



