344 FLORA NIGRITIANA. 
The remaining Onagrariee described as West Tropical African 
are Jussiea stolonifera, Lepr. et Perr., and J. altissima, Lepr., 
Prieurea Senegalensis, DC., considered by Guillemin and Per- 
rottet as another species of Jussiea, and Isnardia multiflora, 
Guill. et Perr., all from Senegal. 
LI. LYTHRARIEÆ. 
There are no specimens belonging to this Order either in the 
Niger collection or in those of Don from West Tropical Africa, 
although no less than fifteen species are enumerated in the 
Senegambian Flora, viz. : Ameletia tenella and elatinoides, (both 
described under Ammannia), Ammannia filiformis, DC., A. Se- 
negalensis, Lam., A. auriculata, Willd., A. gracilis, Guill. et 
Perr., A. salsuginosa, Guill. et Perr., A. floribunda, Guill. et 
Perr., A. pruinosa, Guill. et Perr., A. crassicaulis, Guill. et 
Perr., A. aspera, Guill. et Perr., Nesea erecta, radicans and 
Candollei, Guill. et Perr., and Lawsonia alba, Lam. 
LII. TAMARISEIN.X. 
This small Order or genus is also, in West Tropical Africa, 
_as far as hitherto known, confined to Senegambia, from whence 
a species has been deseribed under the name of Tamarix Sene- 
galensis, but which is probably, as suggested by Webb, a mere 
variety of the T. Gallica, so widely diffused over South Europe, 
North Africa, and the temperate regions of Asia. 
LIII. Menasromacez. 
Nearly the whole of the West African plants of this Order 
belong to the tribe Osbeckiew, and though hitherto chiefly 
referred to the two Asiatic genera, Osbeckia and Melastoma, 
a closer examination shows them to belong to groups, gue 
or sectional, perfectly distinct from both the Asiatic and Ameri- 
ean ones, although perhaps nearer allied to the former. The 
chief characters which separate them from Osbeckia and Melas- 
foma, as now limited, will be best seen from the following 
Synopsis : 
