NORTH AMERICAN BATRACHIA AND REPTILIA. 
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FAUNAL REGIONS OF UNITED STATES. 
Austroriparian Region. — Bordered on the south and east by 
the Gulf of Mexico and the Atlantic; on the north and 
west by a line extending south through the eastern part of 
North and South Carolina, west through upper Georgia and 
Alabama, north through the western part of Tennesssee and 
Kentucky to Southern Illinois, west and south to Indian 
Territory, and across the western corner of Texas to New 
Mexico and the Rio Grande. It includes three districts : the 
Floridan — the southern portion of Florida; the Louisian- 
ian — from the Floridan to Texas; the Texan — Texas. 
Eastern Region — Bordered on the south by the Austroriparian ; 
on the east by the Atlantic; on the west by a line running 
north from the northeast corner of Indian Territory to 
the southeast corner of Dakota, thence northwest. 
Pacific Region — Bordered on the east by the Sierra Nevada 
mountains; on the west by the Pacific; on the south by 
Lower California. 
Lower Californian Region — Occupies the peninsula of that name. 
Central Region — Bordered on the east and north by the East- 
ern; on the west by the Pacific; on the south by the Aus- 
troriparian and Sonoran regions. 
Sonoran Region — Includes parts of Nevada, New Mexico, Ari- 
zona, and Sonora in Mexico. 
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