ZYGOPHYLLACE.E. (bEAIN^-CAPER FAMILY.) 67 



Order 31. BALSAMINACE^^. (Balsam Family.) 



Smooth and succulent annual herbs, with undivided exstipulate 

 leaves, and irregular hypogynous pentandi'ous flowers. — Sepals 5, 

 colored, deciduous ; the two inner (and upper) ones united, the lowest 

 large and saccate. Petals 4-5, distinct or united. Stamens 5, co- 

 herent above. Ovary 5-celled, the cells 2 - several-ovuled. Fruit 

 capsular or drupaceous. Seeds anatropous, without albumen. Em- 

 bryo straight, with thick cotyledons. 



1. IMPATIENS, L. Jewel- Weed. 



Lowest sepal saccate and spurred. Petals 4, united by pairs. Filaments 

 short, with a scale on the inner face. Capsule 5-celled, bursting elastically 

 into 5 valves. Placental central, persistent. — Stems branching, somewhat 

 pellucid. — Leaves serrate. Peduncles axillary, 1 - several-flowered. Earliest 

 flowers fruiting in the bud. 



1. I. pallida, Nutt. (Pale Touch-me-not.) Leaves ovate or oval, 

 obtusely serrate, membranaceous ; flowers pale yellow ; lower sepal slightly 

 spotted, dilated, open, tipped with a short recurved spur. — Wet shady places. 

 July - Sept. — Stems 2° - 4° high. 



2. I. fulva, Nutt. (Spotted Touch-me-not.) Flowers deep orange; 

 lower sepal conical, conspicuously spotted, tipped with a rather long recurved 

 spur; otherwise like No. 1, but with smaller flowers. — Shady swamps. 

 July - Sept. 



Order 32. ZYGOPHYLLACE^E. (Pveax-Caper Family.) 



Herbs, shrubs, or trees, with hard wood, opposite pinnate dotless 

 stipulate leaves, and regular hypogynous mostly decandrous flowers. — 

 Sepals and petals 5-6, imbricated or convolute in the bud. Stamens 

 distinct, often appendaged. Ovary 2 - 12-celled, with the styles united. 

 Capsule composed of 2 - 12 indehiscent carpels, which separate from 

 each other and often from a central axis at maturity. Embryo straight. 

 Cotyledons flat. Radicle superior. 



Synopsis. 



1. TRIBULUS. Carpels 5, transversely few-celled, few-seeded. Herbs. 



2. KALLSTROMIA. Carpels 10, 1-celled, 1-seeded. Herbs. 



3. GUAIACUM. Carpels 2-5, compressed, 1-seeded. Trees. 



1. TRIBULUS, L. 



Sepals .5, imbricated in the bud, deciduous. Stamens 10. Ovary S-celled, 

 with 3-5 suspended ovules in each cell. Carpels of the fruit 5, spiny on the 

 back, transversely divided into 2-5 one-seeded cells, separating at maturity, 



