120 
INTRODUCTION. 
species now supposed peculiar to itself, as well as other 
introduced species. It possesses a peculiar interest as the 
connecting point between the Fauna of North America 
and that of the West Indian islands. 
Section 2. The Tertiary Region of the Atlantic Coast 
and the Gulf of Mexico. This embraces the eastern 
parts of North and South Carolina and Georgia, the 
whole of Florida not included in the preceding section, 
the southern parts of Alabama and Mississippi, the 
whole of Louisiana, and parts of Arkansas and Texas. 
It extends from the ocean to the point where the rivers, 
falling over the last rocky ledge, reach the level of tide- 
water ; and is a low and humid region characterized by 
extensive swamps and marshes, sluggish streams, and 
wide inlets from the sea. On the streams, the soil is but 
little elevated above the water, vegetation is vigorous 
and prolific, and extensive and almost impenetrable 
cane-brakes prevail. On the higher grounds the soil is 
chiefly sandy, and vast tracts, extending for hundreds of 
miles, are covered by magnificent open forests of gigantic 
pines. Here the traveller may journey for days and 
weeks among the monotonous scenery, and will in vain 
seek relief or change in the unvarying landscape, 
" Where to the north — pine trees in prospect risi ■, 
Where to the south — pine trees assail the skies, 
Where to the east — pine trees obstruct the view, 
Where to the west — pine trees forever grew." 
To a favorable climate there is here superadded the 
concurrent geological influence of a substratum of soft 
