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THE AMERICAN MUSEUM JOURNAL 

 Chrysochlorid,-e. 



Living. South Africa. 



These are known as Cape Golden Moles and take the place 

 of the true Moles in South Africa. A fossil species has been 

 found in the Miocene of Patagonia, indicating that they formerly 

 inhabited both southern continents. 



Adapisoricid.-e. 



Extinct. Lower Eocene. France. Imperfectly known. 



Dl.MYLID.-E. 



Extinct. Lower ]\Iiocene. Europe. 



Only two molars in upper and lower jaw, the second quite small 

 Premolars reduced, no canine. Jaws are exhibited in the table-case. 



IV. RODENTIA, OR GNAWERS. 

 Mice, Squirrels, Beavers, Hares, Porcupines etc. 



Small mammals with claws on the toes, five digits on each foot, 

 the teeth reduced in number, a pair of upper and lower incisors special- 

 ized for gnawing. The gnawmg teeth grow continually from per- 



FIQ. 2». SKULL OF THE RAT 

 The most familiar type of the rodeiitia. Natural size 



sistent pulps, during the lifetime of the animal. They have enamel 

 only on the anterior surface and wear to a chisel-like edge which is 

 continually renewed by the more rapid wear of the dentine 

 behind the enamel. 



The Rodents are the most numerous group of mammals, but 

 they are almost all small. There are probably now more different 



