54 Bird -Lore 



the arid West throughout most of the United States near the iooth meridian, 

 becomes more noticeable the farther south we go. We shall not expect, 

 therefore, to find one transcontinental faunal belt sweeping from ocean to 

 ocean, as in the northern faunas, but must now distinguish between the eastern 

 and western parts of each faunal division. Directly south of the Transition 

 zone the middle warm temperate belt is divided into the Carolinian fauna to 

 the east and the Upper Sonoran to the west. Similarly, the south warm tem- 

 perate belt is divided into the Louisianian fauna to the east and the Lower 

 Sonoran to the west. 



According to Dr. Merriam, the Carolinian fauna extends over the Middle 

 States (excepting mountain areas which belong to the Transition and Boreal 

 faunas), southeastern South Dakota, eastern Nebraska, Kansas, part of 

 Oklahoma, nearly all of Iowa, Missouri, Illinois, Indiana, Ohio, Maryland and 

 Delaware, a large part of West Virginia, Kentucky, Tennessee, and New 

 Jersey, besides parts of Alabama, Georgia, North and South Carolina, Virginia, 

 Pennsylvania, New York, Michigan, and southern Ontario. A peculiar 

 extension of this fauna is found in a narrow arm running up the valley of the 

 Hudson and out upon Long Island and southern Connecticut. Dovetailed 

 into the Alleghanian fauna at so many points and so irregularly toward the' 

 north, and into the Louisianian fauna toward the south, the Carolinian area 

 is of great interest. 



West of the Mississippi River, we find the more arid Upper Sonoran fauna 

 spreading out over a country of entirely different aspect. In eastern Montana 

 and Wyoming, southwestern South Dakota, western Nebraska, Kansas, 

 Oklahoma and Texas, and eastern Colorado and New Mexico, it covers great 

 plains; while in Washington and Oregon it follows the broad valleys of the 

 Columbia, Malheur and Harney Rivers. In California, too, we may find it 

 along the San Joaquin and Sacramento valleys, as well as over the Snake 

 Plains of Idaho, the Sevier and Salt Lake deserts of Utah, while traces of it are 

 found at points in Nevada and Arizona. 



The entire middle temperate belt comprising the Carolinian and Upper 

 Sonoran areas is very rich in forms of vegetable and animal life. It is notable 

 for the long and varied list of crops and fruits which may be successfully grown 

 within its limits, for here warm temperate conditions are at their best, being 

 neither too hot nor too cold. 



The Ruffed Grouse, which has numerous relatives to the North and West, 

 ranges from the Transition zone well down to the south warm temperate in the 

 wooded districts of the eastern United States. Unlike the Snow Bunting, it is 

 a permanent resident wherever it occurs. The Upper Sonoran area has no 

 Ruffed Grouse except along its extreme northern border, so that we may call 

 this species representative of eastern faunal areas in warm temperate latitudes. 



The south warm temperate belt which, as we have noted, is divided into 

 an eastern humid and western arid part, intersected by the great continental 



