220 ONAGRACEZ. 
M. pinnatum Walt. Leaves in whorls of 3’s and 5’s, sometimes 
scattered, the floral linear, pectinate toothed, or cut serrate, the teeth 
comparatively few, 5-12 lines long, gradually changing into the sub- 
merged which are in crowded verticels, the capillary pinnz sparse; 
spikes 3-6 inches long: petals purplish, somewhat persistent, stamens 4, 
very rarely 6: mature fruit about | line long: carpels strongly 2-keeled. 
OrpER XX XVIII. ONAGRACEA. Dumort. Anal. Fam. xxxvi. 35. 
Herbacecus or sometimes shrubby plants with entire or 
toothed leaves, with flowers in the axils or in terminal spikes 
or racemes. Sepals united into a tubular calyx, the hmb 4- 
parted rarely more or less; valvate in the bud. Petals usually 
as many as the lobes of the calyx, and attenuate with them, 
inserted on the summit of the tube twisted in the bud, some- 
times wanting. Stamens as many or twice as many as the lobes 
of the calyx, rarely half as many, inserted with the petals, fila- 
ments distinct; ovary coherent with the tube of the calyx, 2-4-_ 
(or by abortion) 1-2-celled placenta in the axis, style elon- 
gated or filiform; stigma capitate or 4-lobed, fruit capsular 
with mostly loculicidal dehiscence, or dry and indehiscent, 
rarely baccate. Seeds indefinite or solitary in each cell, ana- 
tropous without albumen ; embryo straight. 
Trine I. Jusstem. Limb of the calyx divided quite down 
to the ovary and persistent on a many-seeded capsule. Seeds 
naked. ) 
1. Ludwigia. Petals 4 or none. Stamens 4. Capsules short. 
Tripe II. Onacrem. Limb of the free tube of the calyx, 
when there is any, deciduous from the ovary or capsule. Cap- 
sule loculicidal, few to many seeled. Parts of the flowers in 
fours. 
* Seeds comose at the apex; stamens 8, lower leaves often opposite. 
2. Epilobium. Calyx 4-parted nearly down to the ovary or with a 
short and campanulate tube beyond it. 
* * Seeds not comose: leaves all alternate. 
+ Anthers attached near the middle and versatile. Petals gen- 
erally yellow or white. 
3. Gayophytum. Calyx-tube not produced beyond the ovary; this and 
the membranous capsule only 2-celled. 
++ Stamens all of equal length. 
= Stigma deeply 4-cleft, its segments linear. 
4. Qnagra. Ovules and seeds horizontal, inserted in 2 or rarely in sev- 
eral rows, prismatic-angled. 
5. (nothera. Ovules and seeds asvending in one row; not angled: 
flower-buds erect: tlowers yellow. 
6. Anogra. Ovules and seeds ascending, not angled, in two rows: 
flower-buds drooping, flowers pink or white. 
