TIEREDITARV KN'KMIKS: A CAT WATCHING 

 A GRAY SQUIRRRL 



At one time the gray squirrel was so abund- 

 ant as to make ruinous inroads on the corn 

 and wheat crops of our pioneers. Tn Ohio, a 

 hundred years ago, there was a law requiring 

 each free white man to deliver lOO squirrel 

 scalps every year or pay a penalty of $3. To- 

 day the gray squirrel needs legal protection to 

 Jirevent its extermination. 



The hares have developed long legs for 

 running on open plains, and the weasels 

 have long, slender bodies and an exceed- 

 ing quickness which enables them to fol- 

 low and capture their elusive prey in its 

 burrows and among crevices in the rocks. 



The hairy coat of the mole is short and 

 equal to the finest velvet, while that of 

 the porcupine stands out in strong, sharp 

 spines ; the skin of the armadillo is prac- 

 tically hairless, but forms a bony armor 

 covering its upper parts. 



The front feet of squirrels and most 

 other rodents are slender and used with 

 deftness as hands in manipulating food, 

 while those of the badger and skunk are 

 heavily clawed and strongly muscled for 

 the purpose of digging up their prey. 



The tails of many species are varied 

 in form to serve special purposes. The 

 long-haired tails of tree-squirrels have a 

 plttme-like character, which adds much to 

 the beauty of these attractive animals. 

 The long tails of the kangaroo-rats and 

 the jumping-mice serve as balances for 

 their bodies during long leaps. The ver- 

 tically flattened tail of the muskrat and 

 the broad horizontally flattened tail of 

 the beaver are useful as rudders. Per- 

 haps the oddest of all is the naked pre- 

 hensile tail of the opossum, which coils 

 about branches or other support and thus 

 is a safeguard against a possible fall, and 

 even permits the animal to hang sus- 

 pended by it alone. 



STRANGE ADAPTATIONS TO MEET CONDI- 

 TIONS OE ENVIRONMENT AND 

 COMPETiTlON 



In such ways, by thousands of adapta- 

 tions and modifications of the typical 

 four-footed mammal, are they fitted to 

 their varied modes of life, each so far as 

 possible in some special place of its own. 



The efi:'ect of the pressure of environ- 

 ment and competition upon the various 

 species of mammals in any region could 

 not be better shown than by the kanga- 

 roos of Australia. That continent is oc- 

 cupied by many species of these peculiar 

 mammals, some of which inhabit the 

 open plains like our jack-rabbits in the 

 West; others have learned to climb and 

 live arboreal lives in the tree-tops ; and 

 still other members of this group have 

 become burrowers and live in dens under- 

 ground like some of our native rats and 

 mice. 



From the instances mentioned above 

 it is evident that the mammalian organ- 

 ism is very plastic and has been molded 



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