460 ZOOLOGY 



produces abundant crops, both fruits and 

 cereals, and also sugar beets. 



(c) Columbian or Humid Northwestern Area. In the 

 extreme northwestern part of the United 

 States and adjacent parts of British Columbia, 

 along the coast, the climate is excessively 

 humid. In places the annual rainfall amounts 

 to 100 inches. The forests are most luxuriant, 

 and the country is full of life. The tempera- 

 ture is much more uniform than that of the 

 Coloradian, and there is less sunshine. Many 

 fruit trees do well, and roses and other flowers 

 grow to perfection. 

 Upper C. UPPER AUSTRAL. 



(a) East of the Hundredth Meridian. 



(1) Carolinian Area. Here the traveler from the 



north first meets with the sassafras, tulip 

 tree, hackberry, and persimmon. It is the 

 great corn belt, and is in every way of prime 

 agricultural and horticultural importance. 

 One may travel in it through the states of 

 Ohio, Indiana, Illinois, Missouri, and Kan- 

 sas, reaching the limit in western Kansas. 



(b) West of the Hundredth Meridian. 



(2) Upper Sonoran Zone. The western zone 



corresponding to the Carolinian, but very 

 different on account of the arid climate. 

 It is nearly all open country, with com- 

 paratively scanty vegetation. Under irri- 

 gation it is very prolific, and one may see 

 luxuriant orchards and fields, separated 

 only by a wire fence from desert or semi- 

 desert. The word "Sonoran" is derived 

 from Sonora, a Mexican state. 



