158 PROF. OLIVER ON FOUR NEW GENERA OF PLANTS. 
REBOULIA, Raddi. 
R. HEMISPHERICA, Raddi. 
Hab. Nagasaki, Japan, Oldham 
MARCHANTIA, L. 
M. NITIDA, L. et L. 
Hab. Nagasaki, Japan, Oldham. 
On Four New Genera of Plants of Western Tropical Africa, 
belonging to the Natural Orders Anonacee, Olacinee, Loga- 
niacee, and Thymeleacee ; and on a New Species of Paropsia. 
By Professor Oxrver, F.R.S., F.L.S. 
[Read May 5, 1864. | 
[PrAre XIL] 
In a small parcel of well-selected and well-dried plants, collected 
at Old Calabar by the Rev. W. C. Thomson, recently forwarded 
to the Herbarium of the Royal Gardens at Kew through the 
kindness of Professor Balfour, I find many undescribed species, 
some of which are referable to new generic types. 
Of four new genera included amongst these, and also of a re- 
markably fine new Paropsia, I have now the honour to lay brief 
descriptions before the Linnean Society. I have drawn up these 
descriptions partly from Mr. Thomson’s specimens and partly 
from specimens previously sent to Kew from the same country 
by Mr. Gustav Mann. 
PIPTOSTIGMA. 
ANONACEARUM genus novum. Tribus Mitrephoree. 
Subtribus Pheanthee. 
Cris GEN.— Sepala tria, libera, ovata v. lanceolata, acuta. Petala sex, 
libera, biseriatim valvata ; exteriora sepaloidea, sepalis longiora; inte- 
riora multo majora, tenera, plana v. marginibus reflexis, cirea geni- 
talia erecto-conniventia. Stamina indefinita, supra torum hemi- 
sphæricum dense imbricata; antheris sessilibus, cuneato-oblongis, 
extrorsis, connectivo apice truncato transverse rhomboidali. Car- 
pella 4-6, apice in stigma sessile capitatum depresso-globosum ob- 
scure lobatum pilosum deciduum coalita; ovulis 6-10 in sutura uni- 
v. biseriatis. Fructus ignotus.—Arbores. Folia subsessilia, sub- 
parallele penninervia. Racemi cymosi simplices v. paniculze, ad ramos 
annotinos v. vetustiores nascentes. 
Plate XII. fig. 1. Genitalia and connivent bases of two petals. 2 & 3. 
Anther, front and back. 4. Gynccium. 5 & 6. Vertical and trans- 
verse sections of an ovary. 
ae EEN, nn 
