444 Part IV. Chapter 2. 
ı. Strand, Sand Plain- and Low Flat-Formations. 
Beach Formation. The sandy flat beach in Alabama is almost destitute of 
vegetation. The upper beach is characterized by /fomoea pes-caprae, Sesuvium 
portulacastrum (in shallow salty pools) with Cakile maritima geniculata, both 
frequent in the West Indies, associated with /va zmdricata, Suaeda linearis 
and in Louisiana Salzicornia ambigua and Heliotropium curassavicum. The snow 
white sand along the shore of Mobile Bay and the land-locked Perdido Bay 
are covered by a scattered growth of grasses: Panicum repens, Stenotaphrum 
secundatum, Cenchrus incertus and triduloides var. macrocephalus, Tricuspis 
(Triodia) purpurea. A small group of small shrubs herbaceous plants (Zuphorbia, 
F'roelichia, Paronychia etc.) mingle on the sandy benches with the above, viz., 
Chrysoma (Solidago) pauciflosculosa ‘), Conradina canescens, Polygonella polygama, 
Helianthemum arenicola. 
The middle beach in Mississippi and Louisiana is occupied by Suaeda (Dondia) linearis, Cakile 
fusiformis, Salsola Kali, Cenchrus tribuloides var. macrocephalus, Sesuvium portulacastrum, 
Euphorbia polygonifolia, Oenothera humifusa, Erigeron repens, Heterotheca subaxillaris, Era- 
grostis se rag a, while inside of these are found Ipomoea pes-caprae, I. acetosifolia, Stro- 
phostyles helvola, Canavalia obtusifolia. The upper beach association may at times consist wholly 
of three seen Pani amarum, Ipomoea pes-caprae, I. acetosaefolia. Associated with Panicum 
is Uniola Sa wich on the east coast of Florida and northward is predominat, 
while on the Gulf coast it becomes of secondary re gg Panicum amarum becoming the 
leading grass. Yucca gloriosa occurs on the beach dun 
The strand vegetation of Texas, to Br. consists of the tropie salt grass Monan- 
tochlo& littoralis, forming a dense mat, Salicornia mucronata (= S. Bigelowii), S. ambigua (on 
compoet wet while Borrichia er and Lycium carolinianum are shrubs that grow on 
the erest of the beach. 
Delta Formation. The “passes” of the Mississippi River are broad channels 
of fresh water separated from the waters of the Gulf by an irregular and fre- 
quently narrow strip of land of river deposit. Two associations of plants may 
be recognized. These are the Phragmites-Vigna- and the Spartina- 
Associations, according to LLOYD and TRACY ®?, The former occupies the 
higher levels ad, therefore, the portion of the alluvial bank near the fresh 
water. Prapmirs communis (= P. Phragmites) and Vigna glabra are pP! 
minent associated at times with Salir nigra and vines of Cissus (Ampelopsis) 
arborea. In the swampy ground of the lower levels which border on the salt 
water Spartina polystachya gives character to the vegetation. 
Dune Formation. Hillocks of drifting white sand rise above the beach in 
Alabama. On these dunes Ouercus virginiana makes a scrubby growth ass0- 
ciate with the sand oak Ouercus myrtifolia. These with Ceratiola ericoides, 
Chrysoma, Polygonella intertwined with Smilax auriculata form an association 
of Se bushes, Uniola paniculata grows on the crests and steep sides 
ı) LLovD, Francis E.: Some Points in the Anatomy of Chrysoma paucifloseulosa. Bulletin 
Torrey Botanical Club XXVIIE: 
2) ‚ Francıs E. and Faser, S. M.: The insular ‚Flora of Mississippi and Louisiana. 
Bulletin Toms Botanical Club XXVIII: 80. March ı 190 
BIEREN, a 
