Jan., 1922] UPHOF — PLANTS IN SOUTHEASTERN MISSOURI 
7 
with small pale to greenish-yellow flowers. The former species is commoner 
in the southern counties, whereas the latter is further distributed toward 
the north. They grow either around twigs and stems of shrubs and young 
trees or are to be found without any support on treeless areas. Also Vitis 
rupestris Scheele grows sometimes in similar places. 
Descending the above-described types of barren hills, the plant growth 
becomes different, mainly for two reasons: (i) a higher water content of 
the soil; and (2) a larger percentage of organic matter in the soil, which has 
partly accumulated after heavy rains from higher parts of the hills. 
Tree growth is here entirely different; oaks like Quercus marilandica 
have disappeared, and are replaced by Q. alba and Q. rubra; Juglans nigra L. 
is here commoner; and other new species come to the front, such as Betula 
lenta L., B. nigra L., Carpinus caroliniana Walt., Ostrya virginiana (Mill.) 
K. Koch. Where a little valley is reached through which a little stream 
flows the number of various species of trees becomes high; it can not be 
said that a certain species predominates, as they form a mixture of Populus 
heterophylla L., P. deltoides Marsh., Alnus incana (L.) Moench, Salix nigra 
Marsh., smd Platanus occidentalis L. on very wet and fertile soil; whereas 
further back these are accompanied by Celtis occidentalis L., C. mississip- 
piensis Bosc, Morus rubra L., Gleditsia triacanthos L., Pyrus coronaria 
Mill., Ulmus racemosa Thom., Gymnocladus canadensis Lam. Cercis 
canadensis L., Crataegus sp., Prunus serotina Ehrh., and Madura auran- 
tiaca Nutt. (especially common in the southern counties). Impenetrable 
thickets composed of many species of shrubs and young trees are here prac- 
tically always present; they are frequently composed of whole groups of 
Corylus americana Walt., Sambucus canadensis L., Hydrangea arborescens 
L., Rhamnus lanceolata Pursh, I tea virginica L., and Physocarpus opidifolius 
(L.) Maxim. In the more southern counties, such as Butler and Ripley 
counties, one finds in similar localities species which belong to the southern 
part of the state, among which I mention in the first place Neviusia alabam- 
ensis Gray, which the writer found in a single individual about 12 kilo- 
meters west of Poplar Bluff growing in a southeastern exposure on a 
somewhat sandy-loam slope of a small hill near the bank of a little creek; 
previously this species has been found only in a few localities in the state 
of Alabama. Decumaria barbara L. has been found along the bank of a 
little streani (Davis Creek) in Carter County, in but three individuals. 
Along such creeks and little river valleys there are a great many dif- 
ferent kinds of climbing plants, especiaWy A mpelopsis quinquefolia L., Cissus 
stans Pers., Vitis cinerea Engelm., V. riparia Michx., V. aestivalis Michx., 
Phus Toxicodendron L., Tecoma radicans (L.) Juss., and Menispermum 
canadense L. Along the lower parts of the slopes and near creek beds is 
Gelsemium sempervirens (L.) Ait. f., a little vine of the southern states 
which sometimes occurs in some parts of Butler and Ripley counties; on 
the other hand, I was never able to find it in the more northern counties 
