203 PRACTICAL BOTANY. 



bluish, or white, much exceeding the calyx, often hairy in- 

 side. Anthers linear. Houstonia, Wood. 



( Oldenlandia, Grray.) 

 534. (509.) Leaves in whorls of 4 to 6, linear, or ob- 

 lanceolate, obtuse ; the margins and the midrib rough. 

 Corolla-lobes and stamens mostly 3. 



(529) Galium trifidum, L. 



Leaves opposite 535 



«>35. Calyx-limb at first small and involute, at length 

 evolving a pappus of plumose bristles. Corolla funnel-form, 

 5-cleft, commonly evidently gibbous near the base. Fruit 

 1 -celled, 1 -seeded. Flowers in umbel-like, close cymes, pink, 

 rose-color or white, sometimes imperfectly dioecious, or 

 dimorphous. Leaves mostly pinnately divided. 



Valeriana (878). 



Calyx 1- to 5-toothed, or cup-shaped, G-cleft or 



6-toothed at the summit. Stamens 3 (rarely 2). Fruit 



3-celIed. Flowers in dense, terminal cymelets, white or 



bluish. Leaves entire or toothed, oblong or linear, sessile. 



Fedia, Gajrtn. 

 ( Valericmella^ D. C.) 



530. (508.) Corolla-tube split down to the base on one 



side. Anthers, and usually also the filaments, connate. .521 



Corolla not split. Stamens not united 519 



C. INCOMPLETE FLOWERS. 



(537-773.) 



537. (77.) Three to five, twelve, or many flowers in a 

 calycine or coroUine involucre 538 



Involucre to several flowers none, at least not a 

 calycine or corolline 539 



538. Flowers with a perianth, 3-5, all of tbe same sort, 

 in the same 5-lobed, open, funnel-form, pubescent involucre, 

 which is thin and reticulated in fruit. Tube of the perianth 

 bell-shaped, rose-color or purple ; its limb deciduous. Sta- 

 mens (in each flower) usually 3. Style filiform. Stem 

 repeatedly forked. Leaves oblong-ovate, triangular, or 

 cordate, opposite. Oxybaphus nyctagineus, Nees. 



Flowers greenish, with an obsolete, or minutely 4- 

 toothed calyx, 4 petals, 4 stamens, and a 1- styled ovary ; 



