TAMACEAE 291 
b. Leaves glaucous ; blades 24-35 mm. broad. 5. H. occidentalis. 
B. Seapes terminated by a single flower: bulbs 1-2.5 cm. in diameter. 
Perianth-tube over 7 cm. long: staminal crown with free tips between 
the filaments. 6. H. Palmeri. 
Perianth-tube less than 5 cm. long : staminal crown truncate between the 
filaments. 7. H. humilis.. 
l. Hymenocallis Caymanénsis Herb. Bulb large, with a short neck : leaf-blades 
linear-oblong, 3-8 dm. long, 6-8 cm. broad, obtuse, tapering somewhat towards the base : 
flowers 6-12 together at the top of the scape: perianth-tube 13-15 cm. long ; lobes 10 cm. 
long: staminal crown funnel-shaped, 2.5 cm. long: ovules 2 in each cavity. 
In sand or sandy soil, Florida and the West Indies. 
2. Hymenocallis Caribaéa (L.) Herb. Bulb subglobose, 7-10 cm. in diameter: 
leaf-blades linear-oblong, about 4 dm. long, 4.5 cm. broad or more, scarcely tapering either 
way, acute : scape acutely angled : flowers 6-12 together, terminating the scape : perianth- 
tube 5-10 cm. long ; lobes 7-9 cm. long : ovules 2 in each cavity. 
In sand or sandy soil, Florida and the West Indies. 
3. Hymenocallis rotàtum (Ker.) Herb. Bulb ovoid, 4-5 cm. in diameter, with a 
prolonged neck and copious stolons : leaf-blades linear, 3-5 dm. long, less than 2.5 cm. 
broad, bright green : flowers 2-6 together, terminating the scape : perianth-tube 7.5-10 cm. 
long ; lobes linear, about as long as the tube: staminal crown about 2.5 cm. long, very 
rotate : ovules 2 in each cavity. 
In low places or sandy soil, North Carolina to Florida. 
4. Hymenocallis Galvestonénsis Baker. Bulb relatively large : leaf-blades linear, 
4-6 dm. long, 2-2.4 cm. broad : scape 3-4 dm. tall: flowers 4-6 together, terminating 
the scape: perianth-tube 4-9 cm. long ; lobes 6.5 cm. long. 
In damp places, eastern Texas. 
5. Hymenocallis occidentalis Kunth. Bulbs large: leaf-blades strap-shaped, 
glaucous, 3-5 dm. long, 2.4-3.5 em. broad: flowers 3-6, terminating the scape : perianth- 
ue 6-10 em. long ; lobes linear, about as long as the tube: staminal crown 25-32 mm. 
ong. 
In moist soil or shaded hillsides, South Carolina to Missouri, Georgia and Mississippi. 
6. Hymenocallis Pálmeri S. Wats. Bulb narrowly oblong, 8-24 mm. in diameter : 
leaf-blades linear, 5 dm. long or less, 6-10 mm. wide: scapes 1.5-2.6 dm. tall: flower 
solitary : perianth-tube 7.5-10 dm. long ; lobes nearly as long as the tube : staminal crown 
funnel-shaped, 3-4 cm. long, with acuminate tips between the filaments. 
In sand or sandy soil, Florida. 
7. Hymenocallis hümilis S. Wats. Bulb about 1.8 cm. in diameter: leaf-blades 
linear, 10-15 em. long, about 4 mm. wide: scape shorter than the leaves: flower solitary : 
perianth-tube about 3 cm. long, dilated at the top ; lobes linear, 5 cm. long: staminate 
crown broadly funnel-shaped, 16 mm. long, truncate between the filaments. 
In sand or sandy soil, Florida. 
FAMILY 2. TAMACBAE S. F. Gray. Yam FAMILY. 
Perennial herbaceous or somewhat woody vines, with tuberous or knotted 
rootstocks. Stems twining, unarmed. Leaves often opposite or whorled near 
the base of the stem, alternate above: blades simple, several-nerved and netted- 
veined, petioled. Flowers regular, perfect, monoecious or dioecious, in axillary 
spikes, racemes or panicles. Perianth calyx-like: sepals and petals 3 each, 
partially united. Androecium of 3-6 stamens at the base of the perianth- 
lobes. Gynoecium of 3 united carpels. Ovary 3-celled, inferior. Styles as 
many as cavities in the ovary. Stigmas small. Ovules 1-2 in each cavity. 
Fruit a 3-winged 3-valved capsule, or berry-like. Embryo small, in the fleshy 
or almost cartilaginous endosperm. [Dioscoreaceae Lindl. ] 
1. DIOSCOREA L. 
Herbaceous twining vines, with fleshy or woody rootstocks. Leaves alternate, at least 
above: blades often broadest below the middle and cordate : petioles enlarged at the base. 
Flowers mostly dioecious or monoecious, in spikes, recemes or panicles. Sepals and petals3 
each, partially united. Staminate flowers with 3-6 stamens at the base of the limb of the 
perianth and occasionally with a rudimentary ovary: sepals and petals deciduous. Pistil- 
