ALABAMA FLORA AND ITS SOUTHERN NEIGHBORS. 



Genera common to the flora of eastern Asia and that of Alabama Continued. 



41 



WEST INDIES, MEXICO, SOUTH AMERICA. 



Not less than 290 genera containing nearly 40 per cent of the plants 

 indigenous to the Alabama flora are represented in the West Indian 

 Islands, Mexico, Central America, and more rarely in South America 

 as far south as Argentina. On the western coast of the continent but 

 a few genera occur which have also their home with us. The num- 

 ber stated above is comprised within 22 families. About 140 species are 

 common to Central America, Mexico, and the West Indian Islands. 

 This relationship is most evident between the flora of that part of the 

 State embraced within the Austroriparian area and the flora of the more 

 elevated regions of tropical America with climatic conditions some- 

 what similar to those prevailing in southeastern North America. The 

 flora of the subtropical regions of Alabama exhibits faintly the fea- 

 tures of the vegetation of the neighboring tropics by the presence of 

 a few genera of the epiphytal plant formation (Tillandsia, Epidendron, 

 Poly podium), which in the abundance and variety of its forms consti- 

 tutes one of the most striking characteristics of the tropical vegetable 

 world. A scarcely stronger suggestion of tropical character in our flora 

 is afforded in its arboreal vegetation by the presence of our dwarf 

 palmettos (Sabal, Serenoa) with their short or prostrate trunks. Our 

 deciduous-leaved trees are represented by 10 genera common to both 

 regions, 2 species of oak (Quereus virginiana, Q. breviloba) and 2 

 of hickory (Hicoria pecan, H. myristicaeformis) being common to 

 Alabama and the plains of northern Mexico near the Texan frontier. 

 Our wax myrtle, hop hornbeam, mulberry, elm, box elder, haw, and 

 sweet gum occur in the elevated regions of the eastern declivity of 

 the Mexican Andes. Our evergreen magnolia is in the same region 



