340 Systematik und Pflanzengeographie. 



II. Portulaea. 



* Leaves flat. 



1. P. oleracea, 2. P. retusa, 3. P. lanceolala. 

 ** Leaves terete or subterete. 



4. P. stelliformis, 5. P. halimoides, 6. P. pilosa, 7. P. parvula^ 



III. Lewisia. L. redivia. 



IV. Oreobroma. 



* Root branching, the caudex at the surface of the ground ; 

 nerves of bracts and sepals excurrent, gland-tipped. 

 — Scapes 1-flowered. 



1. O. brachycalyx. 



= Flowers many, ind panicled racemes. 



2. 0. Leana, 3. 0. Columbiana, 4. 0. Howellii, 5. O. 

 cotyledon. 



** Root branching; caudex not rising to the surface of the 

 ground ; flowers few, in a raceme ; excurrent calyx-nerves 

 not gland-tipped. 



6. 0. oppoaitifolia, 7. 0. Tweedyi. 

 *** Root conical or fusiform : caudex : scapes 1 to 3-flowered. 

 8. 0. pygmaea, 9. 0. Nevadensis. 

 **** Root globose ; radical leaves few or : scapes leafy-bracted. 

 10. 0. triphylla. 

 Group III. Herbs ; sepals 2, green-herbaceous : capsule 3-valved, 3- to several- 

 seeded. 



V. Calandrina. 1. C. caulescens, 2. C. Menziesii, 3. C. micrantha, 

 4. C. Breweri, 5. C. ambigua. 



VI. Talinum. 



* Leaves more or less flattened. 



1. T. patens, 2. T. lineare, 3. T. brevifolium. 

 ** Leaves terete : flowers in naked-peduncled cymes. 



4. T. humile, 5. T. spinescens, 6. T. teretifolium, 7. T. caly- 

 cinum, 8. T. parviflorum, 9. T. confertiflorum. 



VII. Claytonia. 



* Sterns one to several from a deep-seated com; leaves all 

 radical except a pair of bracts subtending the racime. 



1. C. Virginica, 2. C. Caroliniana, 3. C. lanceolata, 4. C. um- 

 bellata. 

 ** Stern and leaves from a fleshy crown. 



5. C. megarrhiza, 6. C. arclica. 

 VIII. Montia. 



* Leafy-8temmed annuals. 



— At least the lower leaves opposite. 

 1. M. fontana. 



— Leaves all alternate. 



f Stamens 2 or 3, opposite the smaller pedals ; seeds 

 lenticular, margined, very smooth. 

 2. M. Howellii, 3. M. dichotoma, 4. M. linearis. 

 ff Stamens 5 ; seeds closely striate and transversely lineati. 

 5. M. diffusa. 

 ** Leafy-stemmed perennials, stoloniferous or bulbiferous; racemes 

 terminal and axillary, not involucrate-bracted; petals 5, scar- 

 cely unequal ; stamens 5. 



— Sterns filiform ; leaves alternate ; raceme terminal. 



6. M. parvifolia. 



= Leaves opposite ; racemes axillary. 



7. M Chamissonis, 8. M. Hallii. 



*** Leaves all radical ; stem scapiform ; racemes involucrate ; 

 petals and stamens 5 each. 



— Involucral bracts more or less united into a disk, other 

 and smaller bracts above them. 



9. M. perfoliata, 10. M. rubra, 11. M. parviflora, 12. M. 

 spathulata, 13. M. gypsophiloides, 14. M. lenui/olia. 



