FLORA OF SHELL HAMMOCKS AND CULTURAL FLORA. 133 
open vegetation of low perennials and herbaceous plants of various 
families finds its home on the damp, often bare, ground, which is cov- 
ered with a salty efflorescence. On such bare places the following are 
found: 
Sabbatia stellaris. Tissa imarina, 
Gratiola hispida, Atriplex arenaria. 
Oldenlandia littoralis. Heliotropium curassavicum. 
Monniera monniera (Herpestis monniera) . Kleocharis capitata. 
Lippia cuneifolia. Diistichlis spicata. 
Lippia cunecfolia is a prostrate perennial, with rooting, creeping 
stems. 
In the submerged salt marshes, with a firmer floor, formed by 
deposits of a heavier silt, large-stemmed and broad-leaved rushes and 
grasses prevail, forming a compact halophile association of reeds, with 
deeply submerged stout rhizomes tightly interlaced. The slender, 
pale Spartina patens, with its stiff stems and erect involute leaves, 
chiefly prevails with the tall Se¢rpus robustus and Spartina polystachya, 
and with Kosteletzkya wiry Hnica altheaefolia and [pomoea sagittata. 
Shell hammocks.—On the shore of the sea and of the larger inlets, 
and along the banks of the bayou’s narrow tortuous marine channels, 
heaps of bivalve shells, frequently many yards in length and from 6 to 
15 feet and over in height, are encountered, the accumulation of refuse 
from the food supply which served v race of men unknown to history. 
Large live oaks, aged magnolias, and pignut hickories cover these 
heaps, along with dense copses of the red buckeye, the sea plum, and 
the lime-loving Carolina buckthorn, the last two not known from any 
other locality in the lower pine region. On these shell banks the 
West Indian red cedar (Jun/perus baurbadensis) is frequently found in 
full perfection, the sturdy trunk spreading out its almost horizontal 
branches, with their drooping branchlets, at from 12 to 18 feet above 
the ground. This tree is frequently found on the low hammocks lining 
the shores of the Gulf and its inlets from Mississippi to Florida and 
along the Atlantic shore to Georgia. On the driest summits of the 
shell heaps and on the sandy shores of the open sea, exposed to wind 
and tide, it is frequently of low stunted growth with the trunk divided 
from the base. Prickly pear in large patches frequently spreads 
over the open places; /voleulus alsi‘noides, widely distributed in lit- 
toral regions within the tropics of the New and Old World, has been 
observed on the shell banks of Dauphine Island. Remarkable is the 
never-failing occurrence on these shell banks from South Carolina to 
Texas of Limnodeu ( Thurberia) arkansana in the scanty cover of herbs. 
CULTURAL PLANT FORMATIONS OF THE COAST PINE BELT. 
Of the 8,500 or 9,000 square miles covered by the rolling pine barrens 
and pine flats of the coast plain east of the Escambia and Conecuh 
rivers, not more than about 2 per cent, is under tillage, and west of 
