214 



RUBIACEAE. 



[Vol. III. 



Houstonia 



purpurea L. Large Houstonia. (Fig. 3397.) 



Houstonia purpurea L. Sp. PI. 105. 1753. 

 Hedyotis purpurea T. & G. Fl. N. A. 2: 40. 1841. 

 Oldenlandia purpurea A. Gray, Man. Ed. 2, 173. 1856. 



Perennial, stout, erect, tufted, branched or simple, 

 glabrous or somewhat pubescent, 4 / -i8 / high. Leaves 

 ovate or ovate-lanceolate, sessile, or the lower ones 

 short-petioled, 3-5-nerved and pinnately veined, ob- 

 tuse or acute, Yz'-i' long, 3 // -i5 // wide, the margins 

 often ciliate; flowers in terminal cymose clusters; pedi- 

 cels i // -4 // long; corolla purple or lilac, funnelform, 

 2/ r -/\/ f long, the tube at least twice as long as the lobes; 

 capsule compressed-globose, i^ // broad, somewhat 

 didymous, its upper half free and considerably shorter 

 than the subulate-linear calyx-lobes. 



In open places, Maryland to Kentucky, Georgia and 

 Alabama, especially in the mountains. May- Sept. 

 Houstonia purpurea pubescens Britton, Mem. Torr. Club, 4: 



125. 1894. 



Whole plant densely pubescent. Virginia. 

 Houstonia purpurea calycosa A. Gray, Syn. Flor. 1 : Part 2, 



26. 1878. 



Leaves lanceolate or narrower, firm; calyx-lobes subu- 

 late, 2" -4" long. North Carolina to Georgia, Alabama 

 and' Missouri. Perhaps specifically distinct. 



6. Houstonia ciliolata Torr. Fringed 



Houstonia. (Fig. 3398.) 



Houstonia ciliolata Torr. Fl. N. U. S. 1: 173- l82 4- 

 Houstonia purpurea var. ciliolata A. Gray, Man. Ed. 



5, 212. 1867. 



Perennial, tufted, erect or ascending, 4'-7 r high. 

 Lower and basal leaves petioled, thick, i-nerved, obo- 

 vate or oblanceolate, obtuse, 6 // -io // long, their mar- 

 gins conspicuously ciliate; stem leaves oblong or ob- 

 lanceolate, sessile or nearly so; flowers in corymbed 

 cymes; pedicels filiform, i // -4 // long; corolla funnel- 

 form, lilac or pale purple, about 3" long, the lobes 

 about one-third the length of the tube; capsule little 

 compressed, obscurety didymous, \% ,f wide, over- 

 topped by the linear-lanceolate calyx lobes. 

 > On rocks and shores, Maine (?), Ontario to Michigan, 

 south to Pennsylvania, West Virginia, Kentucky and 

 Arkansas. May-Aug. 



7. Houstonia longifolia Gaertn. Long- 

 leaved Houstonia. (Fig. 3399.) 



Houstonia longifolia Gaertn. Fruct. 1: 226. pi. 49. f 8. 



1788. 

 Houstonia purpurea var. longifolia A. Gray, Man. Ed. 



5, 212. 1868. 



Perennial, usually tufted, erect, glabrous, $'-10' 

 high. Basal leaves spatulate or oblanceolate, ob- 

 tuse, not ciliate, very short-petioled; stem leaves 

 linear or linear-oblong, acute or obtuse, i-nerved, 

 6 // -i2 // long, \"-2y 2 r/ wide; flowers in corymbed 

 cymes; corolla pale purple or nearly white, 2.% ,f - 

 3" long, its lobes about one-third the length of the 

 tube; capsule little compressed, globose-ovoid, 

 about i // in diameter, its upper half free and much 

 exceeded by the subulate calyx-lobes. 



In dry open places, Maine and Ontario to Manitoba, 

 south to Georgia and Missouri. May-Sept. 



