FOUR-O'CLOCK FAMILY 79 



Fruit not ribbed; involucre herbaceous, little if at all enlarging in fruit, not be- 

 coming membranous. 

 Stamens usually 5 ; involucre campanulate, not enlarged in fruit. 



Flowers several in each involucre. 5. QUAMOCLIDION. 



Flowers solitary in each involucre. 6. Hesperoxi.\. 



Stamens 3; involucre rotate, somewhat enlarged in fruit in the manner of the 

 next genus, but not membranous. 7. Allioxiella. 



Fruit ribbed; involucre rotate, in fruit becoming much enlarged and membranous. 



8. Allioni.v. 

 Fruit with two rows of strong tubercles on the back and surrounded by two-toothed 

 infle-xed wings. 9. Wedeliella. 



1. ABRONIA Jiiss. Sand Verbena, Sand Puffs. 



Fruit biturbinate, i. e., tapering at both ends, irregularly ridged or crested. 

 Flowers about 2 cm. long; limb 5-10 mm. wide. 



Bracts broadly obovate, over 1 cm. long. 1. A. fragrans. 



Bracts ovate-lanceolate, less than 1 cm. long. 2. A. nudata. 



Flowers about 1 cm. long; limb 3-5 mm. wide; bracts ovate to lanceolate-ovate, 5-8 

 mm. long. 

 Petioles of the stem-leaves shorter than the very thick blades; plant low, about 1 



dm. high. 3. A. pumila. 



Petioles of the stem-leaves much longer than the moderately thick blades; plant 

 slender, 2-4 dm. high. 4. A. ammophila. 



Fruit turbinate or obpyramidal, i. e., almost truncate above, distinctly winged, the 

 wings very broad above. 

 Plant almost acaulescent; stem and leaves greatly surpassed bj' the long peduncles. 



5. A. nana. 

 Plant with an elongated stem. 



Bracts broadly ovate or obovate, acute or obtusish. 



Stem distinctly viscid-pubescent; leaves scabrous-puberulent; bracts 1-1.5 cm. 

 long. 

 Blades of the stem-leaves elliptic; bracts broadly obovate, 12-15 mm. wide, 



obtusish. 6. A. salsa. 



Blades of the stem-leaves lanceolate; bracts oval, acute, about 6-7 mm. 

 wide. 7. A. fallax. 



Stem finely puberulent or glabrous; leaves glabrous; bracts 5-8 mm. long. 

 Stem puberulent; leaves long-petioled ; bracts 8-15 mm. long. 



8. A. elliptica. 

 Stem glabrous; leaves short-petioled ; bracts 5 mm. long. 9. A. glabra. 

 Bracts oblong-lanceolate or lanceolate, attenuate or cuspidate. 



Stem glabrous. 10. A. lanceolata. 



Stem more or less pubescent. 



Stem puberulent; wings with double lamina, coriaceous. 



11. A. Carletoni. 

 Stem villous; wings with single lamina, membranous. 12. A. villosa. 



2. TRIPTEROCALYX Hook. Sand Puffs. 



Flowers 3 cm. or more long; limb about 1 cm. wide; pedxmcles longer than the leaves. 



1. T. cyclopterus. 

 Flowers 1.5-2 cm. long; limb about 5 mm. wide. 



Stem glabrous or nearly so; peduncles often nearly equalling the leaves. 



2. T. pedunculalus. 

 Stem densely pubescent; peduncles at least in flower much shorter than the leaves. 



3. T. micranthus. 



3. SELINOCARPUS A. Gray. l. S. diffusus. 



4. HERMIDIUM S. Wats. l. H. alipes. 



5. QUAMOCLIDION Choisy. Four-o'clock. l. Q. muUiflorum. 



6. HESPERONIA Standi. l. H. limosa. 



7. ALLIONIELLA Rydb. l. A. oxybaphoides. 



8. ALLIONIA Loefl. Umbrella-wort. 



Leaves cordate to broadly ovate-lanceolate , aU distinctly petioled. 



Leaf-blades cordate or deltoid. 1. A. nyctaginea. 



Leaf-blades ovate, rounded or cuneate at the base. 



Stem glabrous; leaves thin and soft; inflorescence not bracteate. 2. A. floribunda. 

 Stem hirsute; leaves thick and fleshy; inflorescence bracteate. 3. A. polyatricha. 

 Leaves ovate-lanceolate, oblong, or linear, sessile, or only the lower short-petioled. 

 Stem more or less hirsute as well as viscid. 

 Fruit pubescent. 



Leaves ovate or broadly oblong, as well as the stem conspicuously hirsute. 



4. A. hirsuta. 

 Leaves linear-lanceolate, almost glabrous ; stem sparingly hirsute, or glabrous 

 except under the nodes. 5. A. pilosa. 



Fruit glabrous. 6. A. Carletoni. 



Stem glabrous below, not hirsute, viscid-puberulent above. 



