Arkansas-Louisiana Distriet. 455 
minor, Ricciocarpus natans and on the drier shore line Saururus cernuwüs ; 
Sum cicutaefolium. Outside of these Crphalanthus occidentalis abounds. The 
swollen bases of Nyssa uniflora afford a favorable foothold for the epiphytic 
fern Polypodium incanum. The vegetation of the sloughs in the state of Ar- 
kansas is essentially similar to the cypress swamps in Missouri and elsewhere 
in the Mississippi Valley, according to RECORD’). In the Wabash Valley the 
southern cypress Tarodium distichum, Carya (Hicoria) aquatica, Planera aqua- 
ttca, Gleditschia inermis, all of the south, find their northern home and there 
the rare swamp cottonwood Populus heterophylla grows to its largest size. 
Beneath these trees grow Cephalanthus and Lindera. The lizard tail, Saururus 
cernuus is also abundant in low wet spots. 
Pond Formation. Nelumbo lutea occupies the shallow margins of the ponds 
near which grows Polygonum amphibium and in association with these Ponte- 
deria cordata, Echinodorus radicans, Heteranthera reniformis, species of Sa- 
gittaria, Re moscheutos, H. a The floating vegetation consists of 
Nymphaca, Nuphar, Cabomba, Brasenia and party submerged partly floating 
species. Margining the pond grew Cephalanthus occidentalis with its lower 
branches bearded with black tufts of a species of lichen Ramalina. Behind 
the buttonbush stood the tall dark wall of the forest. 
Nelumbium Association. Parallelling the mighty river between the bayous and rivers 
re troughs as one of the characteristic features of the topography?). They are of various extent 
depth and shape forming tracts of wet forest swamp or ee rarely entirely free from water 
or ponds and lagoons more or less shallow usually o or more or less studded with the knees 
and mighty trunks of the cypress Taxodium ae lutea, Nuphar advena grow in 
these pools and in open places Nasturtium (Roripa) lacustre, while Hottonia he is a charac- 
teristic floating plant. 
The cottonwood Populus monilifera (= P. deltoides) is found 
reaching large dimensions ar along the banks of the Mississippi River. 
Hardwood Bottom Formation. Below the bluff in northern Mississippi, 
according to Hilgard (Soils: 492) lies the great Mississippi Bottom with its rich 
soils and varied forest growth. This subdivides into at least three distinct soil 
and vegetation strips, viz., the sandy frontlands, the backlands, whose soils are 
partly the product of modern swamp deposits, partly from the disintegration 
of calcareous clays, and thirdly, the dogwood ridge, a narrow belt of slightly 
elevated land, mostly above ordinary overflows. In the forests covering the 
lower lands which slope back to the swamps and lagoons the cow oak, 
Quercus Michauxii is prominent while the overcup oak O. Zyrata occurs every- 
where in the more or less saturated soil. Here Ziguidambar styraciflua reaches 
its greatest size associated with Carya amara (= Hicoria minima), Sassafras 
offieinale (= 5. Sassafras), Ulmus americana, Carpinus caroliniana, Platanus 
RECORD, SAMUEL ]J.: The Forests of Arkansas. Forest Quarterly V: 296301. 1907. 
Ep. Some river bank Flowers. Botanical Gazette I: 51; also consult Houcu EMERSON: 
The Sanken Lands. Recreation, October 1909 where a description is given of these bayous with 
good reproductions of native vegetatio: 
