290 MISC. PUBLICATION 4 2 3, U. S. DEPT. OF AGRICULTURE 



2. Allionia incarnata L., Syst. Nat. ed. 10, 2: 890. 1759. 



Wedeliella incarnata Cockerell, Torreya 9: 167. 1909. 



Throughout most of the State, 6,000 feet or (usually) lower, April 

 to October. Colorado and Utah to southern Mexico; also South 

 America. 



Trailing-four-o 'clock. A conspicuous plant on open plains, mesas, 

 and slopes, with long trailing stems and showy, rose-purple (occasion- 

 ally white) flowers. 



3. Allionia glabra (Choisy) Standi., Field Museum Nat. Hist. Bot. 



Ser. 8: 10. 1930. 



Allionia incarnata L. var. glabra Choisy in DC, Prodr. 13 2 : 



435. 1849. 

 Wedeliella glabra Cockerell, Torreya 9: 167. 1909. 



Apache, Navajo, Yavapai, and Cochise Counties, 4,000 to 6,000 

 feet, July to October. Western Texas to Arizona, south to Oaxaca. 



7. BOERHAAVIA 



Plants herbaceous, annual or perennial; stems usually branched, 

 often with a viscid band around each internode; flowers very small, 

 mostly in terminal racemes or cymes, the perianth limb campanulate 

 to nearly rotate; fruits obpyramidal or clavate, the ribs sometimes 

 winged, the furrows between the ribs rugose. 



The plants grow usually where exposed to full sunlight, but some- 

 times in open chaparral, flowering in late summer and autumn. 



Key to the species 



1. Fruit pubescent, the hairs more or less spreading; plants perennial, with a 

 woody caudex; perianth carmine or dark red (2). 

 2. Flowers solitary on long slender pedicels; plant glabrous or obscurely 

 puberulent, not glandular 1. B. gracillima. 



2. Flowers in glomerules, sessile or on short pedicels; plant usually densely 



glandular-puberulent in the inflorescence, often more or less hirsute 



below 2. B. CARIBAEA. 



1. Fruit glabrous or with strigose hairs in the furrows; plants annual; perianth 

 not carmine or dark red (3). 



3. Flowers in elongate racemes, these forming a cymose or paniculate inflores- 



cence (4). 

 4. Bracts persistent, more than half as long as the fruit; plant viscid- villous; 



fruit 4- (rarely 5-) angled 3. B. wrightii. 



4. Bracts deciduous, much less than half as long as the fruit; fruit 5-angled (5) . 



5. Flowers crowded; bracts broadly ovate or obovate, usually much 



surpassing the ovary at anthesis; stems conspicuously viscid- 



villous below the inflorescence 4. B. spicata. 



5. Flowers not crowded; bracts lanceolate or ovate-lanceolate, not or 

 scarcely surpassing the ovary; stems not conspicuously villous; 

 species of very similar appearance (6). 

 6. Fruit with narrow ridges and open furrows, these conspicuously 



transverse-rugose 5. B. torreyana. 



6. Fruit with broad ridges and narrow or nearly closed furrows, these 



scarcely, or not conspicuously, transverse-rugose_6. B. coulteri. 



3. Flowers not in racemes, the inflorescence cymose or cymose-paniculate (7). 



7. Inflorescence glandular-villous; bracts large, equaling or surpassing the 



fruit, persistent; flowers short-pediceled or nearly sessile, in dense 



glomerules, these borne on long, slender peduncles; fruit with narrow 



ridges and very broad furrows 7. B. purpurascens. 





