170 AMARANTHACEAE (AMARANTH FAMILY) 



linear-subulate: calyx-lobes carinate-crested: seed 1 mm. broad, lightly retic- 

 ulated. Suaeda depressa erecta Wats. (Dondia erecta A. Nels. Bot. Gaz. 34: 364. 

 1902.) Strongly alkaline soil; from the Dakotas to southern California. 



3. Suaeda depressa (Pursh) Wats. 1. c. 89. Perennial from a deep-set 

 slender root or more rarely annual; branched from the base, the branches 

 decumbent or ascending, 3-^ dm. high: leaves linear, 1-3 cm. long, broadest 

 at base, the uppermost shorter, and broader, becoming ovate: one or more 

 of the calyx-lobes keeled in fruit: seed dull, minutely reticulated. Saline soil; 

 throughout the Rocky Mountain States. 



4. Suaeda Moquinii (Torr.) A. Nels. Perennial from a woody base, with 

 erect herbaceous branches, 3-7 dm. high: leaves linear, subterete, 1-4 cm. 

 long; the floral similar: calyx rather large, deeply cleft: seed finely tuberculate. 

 Suaeda Torreyana Wats. (Dondia Moquina A. Nels. 1. c. 363.) From Colorado 

 and Wyoming to California. 



38. AMARANTHACEAE J. St. Hil. AMARANTH FAMILY 



Ours annuals with simple mostly entire leaves destitute of stipules. Flow- 

 ers small, perfect or unisexual, solitary or clustered, usually subtended by 

 scarious bracts (mostly 3). Perianth of 2-5 either herbaceous or scarious 

 segments (sepals) which are distinct or united at the base. Stamens as many 

 as the sepals, or rarely fewer. Ovary 1-celled, 1-ovuled, utricular in fruit. 

 Seed mostly smooth; the embryo annular. 



Anthers 2-celled; leaves alternate. 



Flowers monoecious or dioecious, all with 3-5 sepals . . . .1. Amaranthus. 



Flowers dioecious; calyx wanting in the fertile flowers . . . .2. Acnida. 

 Anthers 1-celled; flowers perfect; leaves mostly opposite. 



Leaves sessile; flowers spicate ........ 3. Froelichia. 



Leaves petiolate; flowers axillary 4. Cladothrix. 



1. AMARANTHUS L. AMARANTH 



More or less branched annuals, either glabrous or pubescent, with thin 

 veiny pinnately-veined petioled leaves. Flowers small, monoecious, polyg- 

 amous, or dioecious, green or purplish, in axillary or spiked clusters of spike- 

 lets. Staminate flowers usually mingled with the more numerous pistillate 

 ones. Sepals 2-5, distinct or united at the base. Utricle ovate or oblong, 

 2-3-beaked, usually circumscissile. Nearly all the species are troublesome 

 weeds, many of them introduced. 



Utricle circumscissile, the top coming off as a lid. 

 Flowers in dense spikes, mostly terminal; stamens 5. 

 Plants pubescent, at least upward. 



Spikes thick, erect . . . . . . . . .1. A. retroflexus. 



Spikes slender, panicled . . . . . . . . 2. A. hybridus. 



Plant glabrous, or nearly so. 



Spine-bearing in the leaf-axils . . . . . . . 3. A. spinosus. 



Not spine-bearing . . . . . . . . . 4. A. Powellii. 



Flowers in small axillary clusters or spikes; stamens 3. 



Plant erect but bushy-branched . . . . . . . 5. A. graecizans. 



Plant prostrate matted . . . . . . . . . 6. A. blitoides. 



Utricle indehiscent, falling away inclosed in the perianth. 



Bracts not exceeding the sepals 7. A. Torreyi. 



Bracts twice as long as the sepals . . . . . . . 8. A. Palmeri. 



1. Amaranthus retroflexus L. Sp. PI. 991. 1753. Roughish and more or 

 less pubescent; stems erect, stout, 3-12 dm. high, more or less branched: 

 leaves ovate to rhombic-ovate, dull green, with undulate margins, 5-10 cm. 

 long, cuneately narrowed at base and often decurrent on the long petiole: 

 flowers green, monoecious, in stoirt thick crowded erect spikes; the bracts 

 lanceolate and attenuate to a rigid awn, twice as long as the scarious sepals: 

 utricle scarcely equaling the sepals, slightly wrinkled. Now common as a 

 weed everywhere. 



