LYTHRACEJi. (LOOSESTRIFE FAMILY.) 157 



t~ f lowers i/ellnii'. 



9. R. lutea, Walt. Stem at le:;gi.h much branched, 4 angled, bristly; 

 leaves sm.joJii.--h, bristly serrulate, the l.jwer ones oho\ate and obtuse, the 

 upper lanceolate and acute; cymes numerous; calyx short and smooth; 

 flowers sm.ill 1 ii.e barren swamps, Florida to North Carolina, and west- 

 ward. July - August. Stem 1 high. Petals more persistent than those of 

 the other species. 



ORDER 58. LYTHRACE.33. (LOOSESTRIFE FAMILY.) 



Chiefly herbs, with opposite or whorled and entire leaves, without, 

 es. Flowers mostly axillary. Calyx tubular, persistent, 4-7- 

 toothed, free from the 2 -4-celled ovary. Petals as many as the teeth of 

 the calyx and inserted into its throat, deciduous, sometimes wanting. 

 Stamens as many as the petals, or 2-4 times as many, inserted below 

 the petals. Anthers short, introrse. Style solitary. Capsule en- 

 closed in the calyx, 1 - 4-celled, few- or many-seeded. Placentae cen- 

 tral. Seeds anatropous, without albumen. Sinuses of the calyx 

 often appendaged. Stigma capitate, or rarely 2-lobed. 



Synopsis. 



* Calyx regular. 



1. DIDIPLIS. Calyx hemispherical. Petals none. Stigma 2-lobed. Capsule 2-celled. 



2. AMMANNIA. Calyx canipanulate. Stigma capitate. Capsule 4-celled. 



3. LYTHRUM. Calyx cylindrical, striate. Capsule oblong, 2-celled. 



4. NES^EA. Calyx short, even. Capsule globose, 3 - 5-celled. Stamens 10. 



* * Calyx gibbous at the base. 



5. CUPHEA. Calyx tubular, 12-ribbed. Stamens mostly 12. Capsule early ruptured. 



1. DIDIPLIS, Kaf.< 



Calyx hemispherical or campanulate, 4-lobed. Petals none. Stamens 2-4. 

 Style very short: stigma 2-lobed. Capsule globose, 2-celled. A submerged 

 aquatic herb, with long filiform stems, opposite crowded pellucid linear leaves, 

 and minute sessile axillary flowers. 



1. D. linearis, Kaf. Ponds and still water, West Florida to North 

 Carolina, and westward. June - August. Stems l-2 long. Leaves 1' 

 long, acute. Flowers not larger than a pin's head. 



2. AMMANNIA, Houston. 



Calyx globular or campanulate, 4-angled, 4-toothed, the sinuses commonly 

 furnished with a small horn-shaped appendage. Petals 4, small, deciduous, 

 sometimes wanting. Stamens 4, short. Stigma capitate. Capsule globular, 

 4-celled, many-seeded. Low smooth annual herbs, with opposite leaves, and 

 solitary or clustered axillary flowers. 



