37 



forms. The term dog is erroneously applied, as they are 

 more like rats. 



The other genus is represented by the WoODCHUCK 

 (Arctomys), BEAR MOUSE, as the name imports. There 

 are several other species found in the western portions of 

 the continent. 



The rodents are so extremely numerous, it will be im- 

 possible to point out more than a few prominent and 

 representative forms. In order to keep an outline of the 

 classification, which teaches us as near as is possible the 

 relative connection of families, their natural place in the 

 scale of life, we will record each family in place, though 

 we may not find room to dwell upon its members. 



GROUP 29.— The Haplodons, Family Haplodontidce. 

 This family is an American one, having only two species, 

 included in one genus. 



The Sewellel (Haplodon rufus), found in the mountains 

 of California, is the representative. It resembles somewhat 

 a musk-rat, or a very large rat, and is, perhaps, one of the 

 most unfamiliar of American mammals. 



GROUP 30.— The Beavers, Family Castoridce. The 

 well-known and valuable animal that represents this 

 family, is seen here with a piece of his work in the form of 

 a large trunk of maple, which has been cut half through 

 with the intention of felling it. Two species only are known, 

 the European differing sufficiently to constitute a separate 

 species. The picture represents the beavers at work, their 

 dam and houses. 



GROUP 31.— The Dormice, &c, Family Myoxidce. 

 This family includes the Old World DORMICE, and a few 

 other forms; twelve species. 



GROUP 32. — Family Lophiomyida. One very rare ani- 

 mal constitutes this family. The Loi'HlOMVS or CRESTED 

 MOUSE, as the name implies, found in Arabia. 



