NYCTAGINACE^E. (FOtJR-o'OLOCK FAMILY.) 301 



Division III. APETAL.dE. 



Floral envelope consisting only of a calyx (often petaloid) 



or wholly wanting. 



Order 62. NYCTACINACEjE. (Four-o'clock Family.) 



Herbs, with mostly opposite and entire leaves, stems tumid at the 

 joint, a delicate tubular or funnel-form calyx which is colored like a 

 corolla, its persistent base constricted above the 1-celled, 1-seeded ovary, 

 and indurated into a sort of nut-like pericarp ; the stem3 few, slender 

 and hypogynous ; the embryo coiled around outside the mealy albumen. 



* Involucre calyx-like, 3 to 5-cleft or -parted, 1 to 12-fiowered : perianth tubular to funnel- 



form or campanulate. 



1. Mirabilis. Involucre 5-lobed, not changed in fruit. Fruit not angled nor winged, and 



scarcely or not at all ribbed. Stamens usually 5. 



2. Oxybaphus. Involucre 5-lobed, 1 to 5-flowered, in fruit becoming enlarged, thin and 



reticulated. Fruit several-ribbed or angled. Stamens usually 3. 



3. AUionia. Involucre deeply 3-lobed, 3-flowered. Fruit with a double line of tubercles 



on the back, surrounded by a rigid winged margin, toothed and inflexed. Stamens 

 usually 3. 

 * * Involucre of 5 or more distinct bracts, subtending a many-flowered head. 



4. Abronia. Perianth salver-form, including the stamens and style. Fruit wing-angled. 



1. MIRABILIS, L. Fodk-o'clock. 



Stamens as long as the perianth : filaments united at base. Stigma 

 capitate, granulate. Fruit globose to ovate-oblong. — Perennial herbs, with 

 opposite leaves nearly equal in the pairs : peduncles solitary in the axils or 

 paniculate : flowers nearly sessile in the involucres. 



* Involucre usually %-flowered: flowers large: calyx long-tubular or funnelform : 



stamens 4 to 5. 



1. M. multiflora, Gray. Stout and spreading : leaves broadly ovate to 

 ovate-lanceolate, often somewhat cordate at base but decurrent upon the peti- 

 ole : involucre glabrous, campanulate, 5-cleft : flowers pale rose-color to purple, 

 with the tube somewhat greenish, 4 to 2 inches long, fruit marked towards 

 the base by ten shallow furrows and as many intermediate dark lines. — Bot. 

 Mex. Bound. 173. From Colorado to the Rio Grande and westward to 



5. California. 



* * Involucre 3-flowered: flowers rather small: calyx broad-funnelform from a 



short tube: stamens 3. 



2. M. OXybaphoides, Gray. Slender, procumbent, diffuse : leaves all 

 deeply cordate, on rather long petioles, lowest reniform, upper ones acumi- 

 nate : involucre deeply 5-cleft, very viscid-glandular as well as the peduncles 

 i:i the loose panicle. — S. Colorado and southward. 



