14 FLORIDA GEOLOGICAL SURVEY TENTH ANNUAL REPORT. 
The rolling uplands of the northern part of this area, although 
largely cleared at the present time, supported originally a mixed 
timber growth, including short and long-leaf pine and many hard- 
wood trees such as oak, hickory, clog-wood and magnolia. On 
the more level and sandy lands the chief timber growth is the long- 
leaf pine with more or less undergrowth of shrubby deciduous 
trees. Bordering the Apalachicola river are the alluvial swamps 
with a dense growth of hardwood deciduous trees conspicuous 
among which are the magnolia, beech, various oaks, ash, dog-wood, 
cottonwood and hickory. In the ravines and bluffs along the river 
the short-leaf pine grows in abundance. Likewise along these river 
bluffs and in the ravines two trees worthy of special mention, since 
so far as known they do not occur outside of Florida and only in 
this particular section of the State, are the two representatives of 
the yew family, Tumi on taxifolium and Taxns floridana. These 
are two very rare and beautiful conifers, the latter, however, being 
the rarer of the two. 
A detailed study of the vegetation of this area was made by 
Dr. R. M. Harper, and the results were incorporated in his report 
on the Geography and Vegetation of Northern Florida published 
in the Sixth Annual Report of this Survey. Five vegetation types 
were indicated for this area and the plants characterizing each type 
are there listed. 
ELEVATIONS. 
The only precise levels available in this area are bench marks 
established by the U. S. Coast and Geodetic Survey and by the 
U. S. Army Engineers. These are placed at intervals across the 
area from east to west following the line of the Seaboard Air Line 
railway and the Louisville and Nashville railroad, and in a north- 
west-southeast direction following the line of the Georgia, Florida 
and Alabama Railway. In addition to these precise levels the pro- 
files and levels of some of the railroads have been available in de- 
termining elevations. The profile of the Apalachicola Northern 
railroad particularly has been of much service in the geologic 
study of this region. A copy of this profile on a reduced scale will 
be found on the map of this area accompanying this report. All 
the levels obtained have been of material assistance in the study 
of the topography and geology, and the writers wish to express 
