FREE INSTITUTE OF SCIENCE 



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THE LIFE FEATURES OF THE COASTAL PLAIN AND THE PIEDMONT 



contiguous Coastal Plain. Thus the sweet-gum (Liquidambar) is pecuHarly 

 a tree of stiff clay lands and the same is true of other species. The boreal 

 coniferous forest of spruce, fir, and larch and their associate hardwoods — 

 birch, aspen and willow, long enured to low, moist temperatures — would sur- 

 vive as a northern forest belt, while all the old Miocene warm temperate types 

 would survive only to the south of this, and many found the conditions best 

 suited to their development on the border land of the Piedmont and the 

 Coastal Plain. How came the animal life of this forest? 



A brief survey of the bird fauna of eastern North America and its distribu- 

 tion during the breeding season will perhaps throw some light on the history of 

 animal life in this forest region. There is a distinct northern element con- 

 sisting of types more or less wide-spread in both Eurasia and North America 

 and associated apparently with the spread of coniferous boreal woodland. Of 

 these are certain finches, as the Purple Finch (Carpodacus), the Pine Grosbeak 

 {Pinicola), the Evening Grosbeak {Hesperiphona), an American form closely 

 related to the Old World Hawfinch, and the Crossbills (Loxia). Likewise the 

 Creepers (Certhia), the Nuthatches (SiUa), the Titmice (Penthestes), and the 

 Kinglets (Regulus), the corvine birds, as the Crows and Jays, the Wax- wings 

 {Bomhycilla) , the Northern Shrike or "Butcher-bird" (Lanius), and certain 

 other species belong essentially to Palearctic or northern Old World types. 

 Another element of our eastern woodland bird Hfe was derived from the dry 

 plateau region of Mexico and southwestern North America, according to Dr. 

 J. A. Allen.* Our Bluebird {Sialia), the Thrasher (Toxostoma), the Chewink 

 (Pipilo), and the Wild Turkey (Meleagris) are wanderers from this center of 

 development, the majority of the closely allied species being still found in the 

 aforesaid region. The rest of our land bird types are either invaders from the 

 tropics or are indigenous to this eastern region itself. The invasion of tropical 

 forms, like the orioles, the tanagers, the cardinal, the rose-breasted grosbeak 

 and blue grosbeak, the indigo-bird, and certain warblers was probably coinci- 

 dent with the widening Gulf and South Atlantic border of the continent, which 

 became the Coastal Plain. These early estabhshed themselves as breeders 

 throughout this woodland area. The late Arthur Irwin Brown has shown very 

 conclusivelyt that this great southern forest of the Atlantic and Gulf Coastal 

 Plain was a post-glacial center of dispersal of reptiles — an " Ocmulgian " center, 



* "The Auk," 1893, 10, 9. 



t Proceedings of the Academy of Natural Sciences of Philadelphia, 1904, 56, 464. 



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