FLORA NIGRITIANA. 537 
perianthii dimidium æquantia, antheris ovato-oblongis con- 
tiguis erectis filamento sublongioribus. Stirps foeminea non 
visa. 
3. Dioscorea Cayennensis, Lam.—Griseb. in Endl. et Mart. Fl. 
Bras. Diosc. p. 33?—Cultivated on the Nun and Quorra 
rivers, where the bulbs (tubers ?) are the size of a Horse- 
chestnut, but compressed, (Vogel.) 
These specimens, nearly allied to the preceding species, have 
however longer male spikes always solitary in the axils, and the 
stems scarcely prickly or only in the lower part. They agree 
With some old West Indian specimens of a Dioscorea, which 
appears to me to be the D. rotundata, Poit. Dict. Suppl. 3. p. 
139, and answer in every respect to Grisebach's more accurate 
character of D. Cayennensis, except that, as in other allied 
Species, I find only one bracteola besides the subtending bract 
to each flower, or two in the whole, not three. 
4. Dioscorea hirtiflora, Benth. ; caule striato puberulo, foliis 
alternis cordato-orbiculatis subreniformibusve acute cuspidatis 
membranaceis 5-7-nervibus reticulato-venosis supra glabris 
subtus stellato-pubescentibus, spicis masculis laxis subsimpli- 
Cibus fasciculatis hirtis, floribus solitariis subpedicellatis, pe- 
rianthio 6-partito, staminibus fertilibus 3 brevibus, sterilibus 
3 filiformibus ovarii rudimentum trifidum zquantibus.—On 
the Quorra, opposite Stirling, Vogel. 
Ramuli tenues, ut videtur inermes, pilis brevibus fuscis fascicu- 
latis ramosisye conspersi v. glabrati. Folia longiuseule petio- 
lata, 13-2 poll. longa, et sæpe longitudine sua latiora, cuspide 
apicis acutissimo, auriculis baseos rotundatis, sinu in novellis 
angusto in adultis lato; venz parum conspicue; puncte 
Pellucidee in junioribus lineares, demum obscurate. Spice 
mascule graciles, 14-2-pollicares, rhachide floribusque pilis 
Stellulatis canescentibus. Flores demum dissiti, bractea an- 
gusta acutissima, bracteola minuta, apertos non vidi, ala- 
bastrum à lin. longum. Perianthii lacinie 3 exteriores 
Ovatze, extus hirtz ; 3 interiores anguste, glabra, consistentia 
multo tenuiore, Stamina fertilia ad basin perianthii cum 
laciniis interioribus alternantia, filamentis brevissimis, an- 
