50 CIIENOPODIACE.E. Airiijlex. 



7. ATRIPLEX, Touni. 

 Flowers moucecious or (li(ecious. 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- 

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

 Styles 2, flliform. 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 tlie globe, mainly along the sea-coasts or in 

 other saline localities ; a few 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 jdaces. The most obvious 

 specific characters are drawn in many cases from the fruiting bracts, whicli 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. patula. 



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



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



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. 



Fruiting 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 : 



brauches spreading, flexuous. 7. A. eracteosa. 



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 2i lines broad. 9. A. coronata. 

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



ovate-oblong, ojiposite, sessile: decumbent. ]0. A. decumben's. 



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. let^cophylla. 

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



Staminate spikes short, dense: leaves jietioled. 12. A. argentea. 



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



* * * Perennial, mostly dioecious 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. 



