50 CIIENOPODIACE^E. Atriplex. 



7. ATRIPLEX, Tourn. 



Flowers monoecious or dioecious. Staminate flowers without bracts : perianth 

 3 - 5-cleft or -parted : stamens as many. Pistillate flowers 2-bracteate, without 

 perianth or rarely with 2 to 4 distinct hyaline sepals. Bracts erect and appressed, 

 distinct or more or less united, becoming enlarged and enclosing the fruit, the mar- 

 gins at length often dilated and the sides thickened or indurated and muricate. 

 Styles 2, filiform. Fruit compressed ; pericarp thin and membranous. Seed verti- 

 cal, with a thin crustaceous or coriaceous testa. Embryo annular, surrounding copi- 

 ous albumen ; radicle inferior, superior, or lateral. Herbs or shrubs, mealy or 

 scurfy ; leaves alternate or rarely opposite ; flowers usually clustered, axillary or 

 in simple or panicled spikes, the sexes distinct or mingled in the clusters. Obione, 

 Moquin. Pterochiton, Torrey. 



About 120 species, distributed over most parts of the globe, mainly along the sea-coasts or in 

 other saline localities ; a lew cultivated as potherbs. Fully a third of the species is found in 

 the United States, especially in the dry and alkaline portions of the interior and southern regions, 

 forming a considerable part of the characteristic vegetation of such places. The most obvious 

 specific; characters are drawn in many cases from the fruiting bracts, which vary much with age ; 

 hence the satisfactory determination of young flowering specimens may be difficult. 



* Annuals, somewhat succulent and mealy : leaves triangular-hastate, large : bracts distinct, 



mostly triangular or hastate, usually foliaceous-margined. 



Spikes naked : male flowers small : lower leaves opposite : seed a line 



broad. On the coast. 1. A. FATULA. 



Flowers axillary, subdicecious ; male calyx larger, 5-parted : leaves 



alternate, entire : styles included : seed small. Interior. 2. A. PHYLLOSTEGIA. 



Spikes naked : calyx large, 4-parted : leaves alternate, coarsely toothed : 



styles exserted : seed minute. Interior. 3. A. SPICATA. 



* * Annuals, not succulent, mealy or scurfy : leaves smaller : bracts not greatly enlarged, more 



or less united, sessile, rarely triangular or hastate. 



Fruiting bracts very small, ovate, entire, not margined or appendaged. 



Low, very slender : leaves ovate to oblong. 4. A. PUSILLA. 



Fmiting bracts small, cuneate or rounded, herbaceously margined and 



toothed : leaves alternate, not triangular or hastate. 

 Bracts cuneate-orbicular, not margined below the middle, 

 The truncate summit shortly 3-toothed : leaves cordate- ovate, en- 

 tire : erect, rather stout. 5. A. TRUNCATA. 

 Summit rounded, shortly 3 - 7-toothed : leaves oblong, small, en- 

 tire : decumbent, slender. 6. A. MICROCARPA. 

 Margin rounded, gash-toothed : leaves lanceolate, sinuate-dentate : 



branches spreading, flexuous. 7. A. BKACTEOSA. 



Margin rounded, with short blunt teeth : leaves narrowly lanceo- 

 late, entire : erect, slender, virgate. 8. A. COULTERI. 

 Bracts orbicular, surrounded by a gash-toothed margin. 



Erect, stout : leaves lanceolate, entire : bracts 2 to 2 lines broad. 9. A. CORONATA. 

 Fruiting bracts triangular-cordate, coriaceous, not margined : leaves 



ovate-oblong, opposite, sessile : decumbent. 10. A. DECUMBENS. 



Fruiting bracts 2 to 4 lines long, indurated or spongy, rhombic-ovate, 

 united, the convex sides usually conspicuously muricate and 

 the margin toothed. 



Leaves broad obovate to ovate-oblong, alternate, entire : decumbent. 11. A. LEUCOPHYLLA. 

 Leaves triangular-hastate to rhombic-ovate, the lower opposite. 



Staminate spikes short, dense : leaves petioled. 12. A. ARGENTEA. 



Staminate spikes long and slender : leaves sessile : branches distant. 13. A. EXPANSA. 



* * * Perennial, mostly dioacious and woody, densely scurfy : leaves mostly alternate. 



Fruiting bracts small, suborbicular, 



Somewhat spongy, muricate, margin toothed : erect shrub with small 



entire sessile leaves. 14. A. POLYCARPA. 



