354 DIOSCOREACE. 
The genus is in great want of revision. Some two or three years ago we compared 
and described all the species in Kew herbarium from within our limits, in the expec- 
tation of seeing the types of several species only known to us from the descriptions 
before publishing this part ; but we have not been able to see them, and are obliged to 
publish our enumeration inits imperfect form. Itis probable that some of our assumed 
new species are not new, although we have been unable to determine them from the 
published descriptions. The four plates, together with our descriptions, may be useful 
to any one undertaking a monograph of the whole genus. Following the enumeration 
of the species is a rough key to the species which have come under our observation. 
1. Dioscorea brachycarpa, Schl. in Linnea, xvii. p. 109. 
Helmia brachycarpa, Kunth, Enum. v. p. 416. 
South Mexico, near Regla (Ehrenberg). 
2. Dioscorea capillaris, Hemsley, n. sp. | 
Gracillima, foliis ovato-cordatis oblongo-cordatisve acuminatis 7-nerviis subtus puberulis, floribus 
masculinis parvis laxe racemoso-paniculatis, pedicellis brevissimis, staminibus 3 filamentis 
deorsum dilatatis, floribus femineis fructibusque ignotis. 
Herba perennis, tuberosa, volubilis, caulibus filiformibus. Folia alterna, petiolata, membranacea, 
7-nervia, nervis extimis 1—2-furcatis, ovato-cordata vel oblongo-cordata, longe acuminata, acuta, 
24-5 poll. longa, preecipue subtus albido-puberula vel fere glabra. Flores masculini glabri, 
virides (ex Galeottio) luridi (ex Lindenio) 14-2 lineas diametro, laxe racemoso-paniculati 
(racemis interdum simplicibus), panicularum ramuli elongati, fere filiformes, sparse puberuli ; 
pedicelli floribus breviores; bractee pedicellis subzquales; perianthii segmenta oblonga, 
obtusa, patentia ; stamina 8 divaricata, filamentis deorsum dilatatis.-—Dioscorea macrostachya, 
Mart. et Gal. in Bull. Acad. Brux. ix. 2 (reprint, p. 20), nec Benth. 
SoutH Mexico, Cordillera of Oaxaca at 6500 to 7000 feet (Galeotti, 5456), Mirador 
(Linden, 234), Orizaba (Botteri, 567, 571). Hb. Kew. 
Var. glabra, novellis omnino glaberrimis. 
Nicaraeua, Chontales (Tate, 117). Hb. Kew. 
A poor specimen, differing from the Mexican plant in being quite glabrous. 
3. Dioscorea cayennensis, Lam. Encycl. iii. p. 323; Kunth, Enum. v. p. 380; 
Griseb. in Bonplandia, 1858, p. 11. 
Panama (Duchassaing).— West Inpigs ; Guiana; Braziu. 
4. Dioscorea composita, Hemsley, n. sp. 
Glabra robusta, foliis amplis orbiculari-cordatis 9-11-nerviis, floribus femineis spicato-paniculatis, 
paniculis pedalibus, capsula oblonga. 
Herba vel frutex per petiolos scandens, glaber, caulibus crassiusculis leviter angulatis. Folia alterna, 
longe petiolata, subcoriacea, 9-11-nervia, orbiculari-cordata, sinu lato lamina usque ad 7 poll. 
longa et 6 poll. lata, acuminata; petiolus crassiusculus, 2-2} poll. longus, basi apiceque incras- 
satus. Flores feminei spicato-paniculati; paniculze pedales, presertim a basi ramose ; perian- 
thium persistens (post anthesin) crassum, subcarnosum ; segmenta late ovata; staminodia 
minuta; styli supra medium connati; stigmata bifida. Capsula oblonga, 1-1} poll. longa, 
