TRANSACTIONS OF WAGNER FREE INSTITUTE OF SCIENCE 

 44 



THE LIFE FEATURES OF THE COASTAL PLAIN AND THE PIEDMONT 



as he termed it. The significance of faunas, or the regional distribution of 

 groups of species, appears to be a phase in the gradual spread of animal life 

 which accompanied the development of certain tjq^es of vegetation. Thus the 

 Carolinian fauna is clearly related to the Coastal Plain and the contiguous hill- 

 slopes of the southern Piedmont. The entire region is one of diverse habitat 

 elements, as already pointed out. That certain of its animal t3^es tend to 

 spread beyond its generally recognized borders is seen in the breeding ranges of 

 such decidedly austral birds as the wood-thrush, the chewink, the field 

 sparrow, the indigo-bird, the rose-breasted grosbeak, the whippoorwill, 

 the dove, the scarlet tanager, and the orchard and Baltimore orioles which 

 have extended well into the Piedmont region, including its New England por- 

 tion. This group of species is typical of the Alleghanian or transition zone 

 fauna. Furthermore, there is a marked movement of certain Carolinian species 

 into the cleared areas of the upland region. "A fauna," as I have elsewhere 

 remarked,* "is an expression of the temporary adjustment of any group of 

 living beings to given conditions of environment. .... In 

 the sum of its conditioning factors character of vegetation is probably the most 

 important determining influence. . . . . All species tend to 

 spread, as their ancestral types have spread wherever suitable habitats are 

 accessible to them." 



In bringing this paper to an end I feel constrained to conclude with words 

 which I have elsewhere used in an endeavor to portray the relations of a fauna 

 to the geologic history of the land, especially with reference to the formative 

 influences of the last glacial period: "Throughout an immense lapse of time, 

 time that must be reckoned in hundreds of thousands of years, during which 

 the great Keewatin and Laurentide glaciers pushed their ice sheets beyond the 

 present site of the Great Lakes and the Mohawk Valley, forcing southward the 

 animal and plant life into an area of high biotic tension, a wide-spread change in 

 types must have taken place. The most primitive forms have undoubtedly 



disappeared It was a period of profound environmental 



moulding, intensified by the effect of the glaciers on the land and its life. From 

 our limited point of view the array of species and varieties which we see today 

 seem peculiarly stable in their features and their adaptations. But the dynamic 

 influences of environment are ceaseless if inconspicuous. Species and faunas 

 alike are but passing phases in the vast cosmic processes of a continent's 

 history." 



* "The Relations of Genera to Faunal Areas," Trotter. "The Auk," 1909, 26, 221. 



