58 



PLANT LIFE OK ALABAMA. 



crtip can not In- pu^-licil. ami wliidi aUo prfsctits a liarricr (o scNcral 

 trrcs and a iimiilirr of other plants of Soiit licni disl i-il»iitioii tliat un; 

 only nirclv met farther noi'tli. as. for.exanijdf. the willow oak (Qnrmis 

 J>h«'ll<>n), lohlolly pin<' {Piiius fanhi), loni^-leaf pine ( I 'i n us jhiI iisf i-Ik). 

 and cane {AniiidliKirni nuici'Dsjuriint). This line, iv)ui;hly extendine- 

 fioni tlie Atlantic coast atthe mouth of the Chesapeake Bay westward 

 to s(Uith\\t'steiii Missouri and noitherii Arkansas, was located l)y Gray 

 alone- latitude ;'><i ;>(>'. and l)y him I'ee-arded as the line of sepai'alion 

 hetween tile two principal tloral divisions of eastern North America, 

 nainidy. the flora of the northern riiited States and Canada and the 

 flora of the Southern States. In Alabama it is oidy this lower Itelt of 

 the Carolinian area, cMnhracinjj;" the mountain reeion and the lower hills 

 with which >ve are concerned. 



MOUNTAIN KEGION. 



The extreme southern spurs of the Ai)palachian chains l)elone-. with 

 their western and eastern frontiers, to two distinct members of tliis 

 mountain system. Their ditferences in topographical and stratigraph- 

 ical conditions affect visibly the distril)ution and localization of species 

 in the sections traversed by them. 



RANGES OF HILLS OK THE METAMOKPHIC AM) OI.DF.K PAI.KOZOIC STKATA. 



Physhigrapliical features and cl'miate. — The spurs w^hich enter the 

 State at its eastern boundary are the continuation of the most eastcu'ly 

 of the Alleg-henian ranges, and are composed of metamorphic crystal- 

 line rocks skirted \y\ the oldest sedimentary strata. They extend from 

 the Coosa River to the Tallapoosa and include th(^ most elevated parts of 

 the Sttite. The valleys reach an extreme elevation of about 1,000 feet 

 above sea level, and the highest summits of the ridges reach an alti- 

 tude of from 2,0(J0 to 2,400 feet above the Gulf of Mexico. These 

 ridges rise abruptly from the vallej'S and above the lower hills; their 

 steep flanks are covered with the sharp-edged fragments of the sili- 

 ceous rocks Avhich crown their crests with bold (ditfs. 



The locality of Talladega (altitude 800 feet) coincides nearly with 

 the center of this subdivision. The records of daily meteorological 

 observations made at this town for only two successive years ai-e at 

 hand, which are embodied in the following table: 

 DnUt itf temperature {degrees F.) and precipitation {inches) at Talladeya for liro years. 



This mean annual precipitation can be considered as representing 

 that of the whole sulxlivision. with the exception of Lee County, on 

 its southern border, where it rises to 54.4 inches. 



