THE SUKFACE OF THE EAKTH. 



but differs from it in being intersected by large and extensive 

 rivers. 



84. Central America is the tract of land uniting South America 

 with the northern peninsula. Its southern part being not more 

 than 30 miles wide, is denominated the isthmus of Darien or 

 Panama, a town of the latter name being on its western coast. 



IV. UNITED STATES CANADA. 



85. North America, like Europe, is indented with numerous 

 bays, and its northern division has the largest collections of fresh 

 water in the world, consisting of five extensive lakes, called 

 Superior, Michigan, Huron, Erie, and Ontario, which communi- 

 cate with each other, and discharge their water through the 

 River St. Lawrence into the gulf of that name. 



86. Its extent and limits. North America is separated from 

 Asia by Behring Strait on the west, and from the large island of 

 Greenland by Baffin's Bay and Davis's Strait on the north and 

 east. 



A sort of northern archipelago intervenes between this conti- 

 nent and Greenland, into which numerous promontories project, 

 and the waters of which are variously denominated, the largest 

 of these inlets being Hudson's Bay. 



87. Its political divisions. In political geography North 

 150 



