906 REPORT OF THE HARVARD AFRICAN EXPEDITION 
vines, as well as the most fragrant, is the apocynaceous Landolphia sp. that 
bears large numbers of conspicuous white flowers. 
On a muddy flat bordering a creek and which is submerged when the river 
is at its height, grows a species of Cuviera, quite distinct from that collected 
at Monrovia. It is a tall bush or straggling tree about twenty feet high that 
branches four feet above ground and tends to become straggling. The fruit 
when bruised or cut gives off the odor of oil of wintergreen. It is not on that 
account that the species is of interest, rather because of the fact that it is myr- 
mecophilous, the ants being harbored in the green wood of the young shoots. 
In association with Cuviera, and conspicuous because of the zig-zag growth 
of the slender branches, is Tetrorchidium didymostemon. The upper border of 
the mud flat is fringed with a dense thicket of zingiberaceous plants. 
In the original forest, Calpocalyx brevibracteatus attains a height of eighty 
feet or more, and Cloarylon hexandrum, sixty feet, as does also a species of 
Anthocleista, while Milletia lucens reaches forty feet, and its relative, M. Thon- 
ningit, twelve to twenty feet. There are numerous species of the undergrowth 
and of these Ouratea flava is by far the most abundant. Less frequent are 
Salacia leonensis, Olax Linderi, Ouratea Schoenleiniana, Tetrorchidium didy- 
mostemon, and Croton nigritanus, the last a species which attracts attention 
because of the flaming scarlet color of the older and dying leaves. Dorstenia sp., 
a relative of the fig, is rather abundant, but because of the inconspicuousness 
of the peculiar green, flattened flower receptacle, often escapes notice. 
Of the vines and lianes, Rhigiocarya racemifera, Hymenocardia lyrata with 
its peculiar two-winged fruit, Sltephania Dinklager, and Hippocratea velutina are 
not uncommon. Leptoderris fasciculata and Hippocratea Richardiana produce 
stouter and longer vines that climb over relatively tall trees. Atroxima libe- 
rica appears to be a cross between a tall bush and a vine, with the former char- 
acteristic predominant. It starts out as a bush, but the lower branches have 
a tendency to become so elongate as to require support from neighboring bushes. 
An additional species of Draceana has this same tendency. At first it is an 
erect woody herb but soon it becomes necessary for the plant to depend on its 
neighbors for support. 
On the forest floor in the dense shade, Streptogyne gerontogaea, Milbraedia 
paniculata, the former a grass and the latter a member of the Euphorbiaceae, 
both manage to survive despite their none too liberal allowance of light. Rhip- 
salis, a cactus and the only representative of that family of the western hemi- 
sphere in tropical Africa, hangs from the upper branches of trees upon which 
it is epiphytic. Another epiphyte, the staghorn fern, hitherto not observed, 
grows here in relative abundance. 
The second growth is of the usual type with Haronga madagascariensis 
and the common climbing saw-grass only too frequent, and these are seconded 
by Antidesma laciniatum var. membranaceum. Dichapetalum pallidum grows 
over the lower trees to a height of thirty-five feet while Rhigiocarya racemifera, 
R. Chevalieri, Celosia laxa, Psophocarpus palmettorum, and Iodes liberica climb 
over the bushes. Cucwmeropsis edulis also is scandent but appears to occur 
