172 NYCTAGINACEAE (FOUB-O'CLOCK FAMILT) 



3. FROKLICHIA Moencb 



Erect woolly or silky annuals, with narrow opposite leaves, perfect 3-bractea 

 flowers in panicled spikes. Calyx tubiilar, 5-cleft at the summit, 2-5-crested 

 on the tube or sometimes tuberculate in fruit. Stamens 5, the united fila- 

 ments fonning a tube 5-cleft at summit and bearing the 1-oelled anthers be- 

 tween the lobes. Ovary ovoid; the utricle indehiscent and inclosed in the 

 stamen-tube. 



Spikes all opposite . . . 1. F. floridana. ' 



Spikes alternate, at least in part 2. F. gracilis. 



1. Froelichia floridana (Nutt.) Moq. in DC. Prodr. IS^: 420. 1849. Stout, 

 suberect, with slender branches, 3-5 dm. high: leaves from oblanceolate 

 below to linear on the pedunculate stem: spikes opposite: fruiting calyx 

 vertically wing-crested. — From Colorado to Texas and Florida. 



2. Froelichia gracilis Moq. in DC. Prodr. IS^: 420. 1849. Similar but 

 smaller and slenderer: leaves Unear or the lower spatulate arid subpetioled: 

 spikes (at least some of them) alternate: fruiting calyx with vertical rows 

 of tubercles or these confluent mto crests. — Colorado to Kansas and Texas. 



4. CLADOTHRIX Nutt. 



Low annual, or erect and woody at base, with small rounded entire petiolate 

 leaves. Flowers 3-bracted; bracts concave, hyaline. Perianth of 5 erect equal 

 oblong rigid-scarious sepals, somewhat pilose with verticillately branched 

 hairs. Anthers large, oblong. Utricle ovate-globose, indehiscent. 



1. Cladothrix lanuginosa Nutt. Moq. in DC. Prodr. IS^: 360. 1849. Pros- 

 trate or ascending, diffusely branched: leaves round-obovate to rhomboidal, 

 more or less attenuate at base, often in threes: flowers mostly in pairs: sepals 

 twice longer than the broader hairy-tipped bracts. — From S. Cahfornia east- 

 ward through S. Colorado to Arkansas and Texas. 



39. NYCTAGINACEAE Lindl. Four-o'clock Family 



Herbs, with stems more or less swollen at the joints and mostly opposite 

 entire leaves. Calyx tubular or funnelform, 4-5-lobed, usually delicate in 

 texture and more or less colored like a corolla, its persistent base constricted 

 above the 1-celled, 1-seeded ovary and becoming indurated into a nut-like 

 pericarp. Corolla wanting. Flowers umbellately clustered and subtended 

 by an involucre (in our genera). Stamens few, slender. Fruit grooved, 

 ribbed or winged. — {AUioniaceae.) 



Involucral bracts more or less united. 



Involucre unchanged in fruit .^.^, , , , , , .1. Mirabilia. 

 Involucre accrescent and veined in fruit. 



Involucre 5-lobed ..•••.,,,,,2. Allionia. 



Involucre 3-lobed ,.3. Wedelia. 



Involucral bracts distinct •..•••.,••4. Abronia. 



1. MIRABILIS L; FotJB-o'cLOCK 



Perennial herbs with opposite leaves nearly equal in the pairs. Peduncles 

 solitary in the axils or pamculate. Involucre calyx-like, 5-lobed, not changed 

 in fruit, 3-6-flowered. Perianth tubular-funnelform. Stamens as long as the 

 perianth; the filaments united at the base. Stigma capitate, granulate. 

 Fruit globcn to ovate .blong, smooth or only sii^tly ribbed or furrowed. 

 — (Inolud- Alicnielia Rydb.) 



Inflorescencv i,-" —ate . . 1. M. multiflora. 



Inflorescence vei-y g!?-"'"'" ^ubesoent . . , , . , Z. M. oxybaphoides. 



