828 LYTHRACEAE 
Leaves mostly opposite. 
Leaf-blades oblong to orbicular or rarely cuneate. 
Hypanthium trumpet-shaped : leaf-blades short-petioled. 1. L. Vulneraria. 
Hypanthium tubular or nearly so: leaf-blades sessile. 2. L. ovalifolium. 
Leaf-blades linear. 3. L. lineare. 
Leaves mostly alternate. 
Leaf-blades narrowed at the base. 
Larger leaves with linear blades: sepals broadly triangular, the accessory 
teeth short and stout. , 4. L. linearifolium. 
Larger leaves with elliptic or lanceolate blades: sepals mucro-like, the acces- 
sory teeth subulate. 
Leaf-blades thick, those of the branches numerous, approximate, mostly 
less than 1.5 em. long : hypanthium 6-8 mm. long. 5. L. lanceolatum. 
Leaf blades thin, those of the branches few, mostly over 1.5 em. long: hy- 
panthium 3-5 mm. long. 6. L. Curtissii. 
Leaf-blades rounded or cordate at the base. 7. L. alatum. 
1. Lythrum Vulnerària Ait. Stems more or less creeping, spreading or ascending, 1-12 
dm. long. very slender: leaves opposite; blades leathery, oblong to oval, 0.5-1 cm. long, 
obtuse, flat, rounded or cordate at the base, short-petioled: flowers axillary, about 1 cm. 
broad: hypanthium 5-6 mm. long, short-pedicelled, slightly trumpeted-shaped, fluted : 
sepals low, mucronate, the accessory teeth subulate, ascending: petals purple, cuneate- 
obovate, obtuse: stamens in short-styled flowers, exserted : capsules 4-7 mm. long. 
On margins of ponds and swamps, Florida to Texas and Mexico. Spring to fall. 
2. Lythrum ovalifólium Engelm. Stems erect or decumbent, 1-3 dm. tall, simple 
or branched, the branches very slender: leaves opposite; blades oblong to orbicular- 
oblong, or the lower ones cuneate, 1-1.5 cm. long, obtuse or acutish, entire, sessile: flowers 
axillary, 7-9 mm. broad: hypanthium nearly tubular, 4 mm. long, fluted-angled : sepals 
short, apiculate, shorter than the subulate accessory teeth : petals violet, cuneate, rounded at 
theapex, spreading : stamens exserted : capsules narrowly oblong, included : seeds 0.4 mm. 
in diameter. [L. alatum var. pumilum A. Gray.] 
In damp soil, Texas. Spring and summer. 
3. Lythrum lineare L. Stems wand-like, 3-12 dm. tall, 4-angled, branched above : 
leaves opposite; blades linear, 1-4 cm. long, leathery, acute, or the lower ones obtuse, 
slightly revolute, sessile: flowers dimorphous, 7-8 mm. broad : hypanthium rather short, 
about 4 mm. long, trumpet-shaped, fluted : sepals triangular, awn-tipped, about as long as 
the short horn-like accessory teeth : petals cuneate or cuneate-oblong, rounded at the apex, 
pale purple or pink: stamens included, or exserted in the case of short-styled flowers: 
capsules oblong-clavate, hardly 4 mm. long: seeds 0.8 mm. long. 
In or near salt meadows, New Jersey to Florida and Texas. Summer. 
4. Lythrum linearifólium ( A. Gray) Small. Stems slender, simple, or branched at 
the base or above, angled, the branches erect or spreading : leaves alternate, firm ; blades 
linear or linear-oblong, acute or acutish at the apex, slightly revolute, sessile : hypanthium 
trumpet-shaped, 5 mm. long: sepals broadly triangular, acute, their accessory teeth short 
and stout : corolla nearly 1 em. broad : petals obovate, rounded at the apex, purple, drying 
violet-purple: capsules narrowly clavate-oblong. [L. alatum var. linearifolium A. Gray. J 
In moist ground, Texas to Arizona and Mexico. Spring to fall. 
5. Lythrum lanceolàtum Ell. Stems erect or ascending, 6-16 dm. tall, sharply 
angled or slightly winged, usually with numerous strongly ascending branches: leaves 
alternate or some of the lower ones opposite ; blades elliptic to linear-elliptic, 1-6 cm. long, 
acute at the apex, narrowed to the sessile base, those of the branches numerous, approXi- 
mate mainly about 1 cm. long: hypanthium slender, 6-8 mm. long, fluted : sepals mucro- 
like, acute, their accessory teeth subulate, ascending : corolla violet-purple, 8-10 mm. broad : 
petals rose-purple, obovate or cuneate-obovate, obtuse : stamens included : capsule narrowly 
oblong, included : seeds 0.8 mm. long. 
Inlow grounds and in swamps, South Carolina to the Indian Territory, Florida and Texas. Summer. 
6. Lythrum Curtíssii Fernald. Similar to L. lanceolatum in habit, but less rigid. 
Stem wing-angled, the branches pliable: leaves mainly alternate ; blades relatively thin, 
those of the main stem 2-5.5 cm. long, those of the branches relatively few, distant, usuaily 
about 2 em. long: hypanthium 3-5 mm. long: sepals somewhat longer than the bristle- 
like teeth : petals pale purple. 
In low grounds and marshes, Georgia and Florida. Summer and fall. 
7. Lythrum alàtum Pursh. Stems erect or ascending, 3-13 dm. tall, angled and 
often slightly winged, much branched, the branches erect or ascending: leaves sien 
or some of the lower ones opposite; blades lanceolate, oblong or ovate-lanceolate, 1-9 
em. long, acute at the apex, rounded or cordate at the more or less clasping base, Sesst'e: 
flowers conspicuous, dimorphous, on short 2-scaled pedicels: hypanthium 5-8 mm. long, 
