T52 RUBTACEAE (MADDER FA:NrTLY) 



1. C. occidentalis L. Sranoth ; leaves petioled. ossentiiilly .i,'labroiis, ovate 

 or lanceolate-oblong, pointed, opposite or wliorled in threes, with short interven- 

 ing stipules. — Swamps and along streams, s. w. N. B. to w. Ont., and south w. 

 July, Aug. — Usually a shrub with us, rarely arborescent and 5 or 6 m. high. 

 (Mex., W. I.) 



Var. pubescens Raf. Branchlets and at least the lower surfaces of the leaves 

 soft-pubescent. — 111. to Ga., La., and Tex. 



8. houst6nia l. 



Calyx 4-lobed, persistent ; the lobes in fruit distant. Corolla usually much 

 longer than the calyx-lobes, the lobes valvate in tlie bud. Anthers linear or 

 oblong. Style 1 ; stigmas 2. Ovary 2-celled. Pod top-shaped, globular, or 

 didymous, thin, its summit or upper half free from and projecting beyond the 

 tube of the calyx, loculicidal across the top. Seeds 4-20 in each cell, pitted. — 

 Small herbs, with .short entire stipules connecting tlie petioles or narrowed bases 

 of the leaves, and cymose or solitary and peduncled flowers ; the.se dimorphous, 

 in some individuals with exserted anthers and short included style ; in others 

 the anthers included and the style long, the stigmas therefore protruding. 

 (Named for Dr. William Houston^ an English botanist, who collected in tropi- 

 cal America. ) 



* Small and delicate, vernal-floinerimj ; pednnclen l-floicered ; corolla salver- 

 form; upper half of the broad and somevshat 'I-lohed pod free ; seeds globu- 

 lar, with a very deep round cavity occupyiny the inner face. 



■*- Perennial by delicate filiform creeping rootstocks or creeping stems ; pedun- 

 cles filiform, 2-5 cm. long. ' 



1. H. caerulea L. (Bluets, Innocence.) Glabrous; stems erect, slender, 

 sparingly branched from the base, 0.5-2 dm. high ; leaves oblong- spatulate, 0-9 

 mm. long ; peduncle Aliform, erect ; corolla light blue, pale lilac or nearly white, 

 with a yellowish eye, the straight slender long-exserted tube much longer than 

 its lobes or than those of the calyx. — Moist and grassy places, N. S. to Ga., 

 w. to Ont., Wise, and Ala.; producing from early spring to midsummer its 

 delicate little flowers. 



Var. Faxon5nim Pease & Moore. Corolla white, with a prominent yellow 

 eye, the tube shorter, gradually expanding to the limb. — Alpine regions. 

 White Mts., N. TI. 



2. H. serpyllifblia Michx. Like the preceding species, but the filiform stems 

 prostrate, extensively creeping and rooting; leaves orbicular to ovate, 4-9 mm. 



long ; corolla rather larger, and deep violet-blue. — Along 

 streamlets and on mts.. Pa. to Tenn. and S. C. 



■t- •*- Winter-annuals, branching chiefly from the base; root 

 simple ; peduncles much shorter. 



8. H. patens Ell. Stems 2 cm. to at lerfgth 1 dm. high, 

 with ascending iHanches and erect peduncles ; leaves spatu- 

 late to ovate ; corolla much smaller than that of no. 1, 

 violet-blue or purplish without yellowish eye, the tube longer 

 than its lobes, twice the length of the calyx-lobes. (H. minor 

 Britton.) — Dry or sandy .soil, Va. to 111. and Mo., s. to Ga. 

 and Tex. Fig. 918. 



4. H. minima Beck. More di^nse, commonly scabrous ; 



stems at length much branched and spreading, 2-10 cm. 



high ; lowest leaves ovate or spatulate, the upper oblono 



913 H nateii-* "^ nearly linear ; earlier peduncles elongated and spi-eading 



in fruit, the later ones short ; tiibe of the purplish corolla 



not longer than its lobes or the ample calyx-lobes (8 mm. long). — Dry hills, 



s. e. la. to Tex. Mar.-May. 



