38 NORTH AMERICAN FLORA [VOLUME 32 
sule; corolla funnelform, 5 mm. long, glabrous outside, the lobes oblong, obtuse, shorter than 
the tube, villous within; capsule subglobose, 1.5 mm. long and nearly as wide, half inferior, 
rounded or truncate at the apex, the free portion scaberulous; seeds minute, oblong, concavo- 
convex, peltate, scrobiculate, black. 
TYPE LocaLity: Crevices of rocks on the San Pedro River, Texas. (State given erroneously as 
Arizona in the original description.) 
DISTRIBUTION: Western Texas. 
35. Houstonia Palmeri A. Gray, Proc. Am. Acad. 17: 202. 1882. 
Erect perennial, 5-15 cm. high, the stems few, much branched, scaberulo-puberulent or 
glabraie, the internodes mostly longer than the leaves; stipules minute, triangular or subtrun- 
cate, usually cuspidate, denticulate; leaves sessile, linear or linear-filiform, 5-18 mm. long, 
obtuse or acute, thick and somewhat rigid, glabrous, the margins revolute; flowers very laxly 
cymose or axillary, the pedicels stout, 5-20 mm. long, ascending; hypanthium at anthesis less 
than 1 mm. long, glabrous; calyx-lobes linear or lance-linear, acute or subobtuse, more than 
twice as long as the hypanthium, ciliolate, in fruit usually much longer than the capsule; 
corolla salverform, 8-10 mm. long, purplish, glabrous outside, the lobes oblong, obtuse, 
slightly shorter than the tube, white-villous within; capsule subglobose, 2.5—-3 mm. long and 
about as wide, slightly compressed, half or slightly more than half inferior, rounded or sub- 
retuse at the apex, the free portion scabrous; seeds crateriform, about 1 mm. long, rounded- 
oblong, with a conspicuous hilar ridge, coarsely scrobiculate, black. 
TYPE LOCALITY: In the mountains east and south of Saltillo, Coahuila. 
DISTRIBUTION: Coahuila. 
DOUBTFUL SPECIES 
HEDYOTIS? ROSEA Raf. Fl. Ludov. 77. 1817. Described from Louisiana, but Rafi- 
nesque’s name is based upon a description by another author, the identity of whose plant is 
wholly doubtful. 
HOUSTONIA BILOBA Raf. New FI. 4: 101. 1838. Described from ‘‘Arkanzas.’’ Prob- 
ably either H. patens Ell. or H. minima Beck. 
HOUSTONIA RETICULATA Raf. New Fl. 4: 102. 1838. Described from Alabama; not 
identifiable from the description. 
14. ARCYTOPHYLLUM* Willd.; Schultes, in R. & S. Syst. Veg. 
Mant.:3: 5; “1827. 
Mallostoma Karst. Fl. Columb. 2: 9. 1862. 
Pseudrachicallis Karst. Fl. Columb. 2: 10. 1862. 
Ereicoctis Kuntze, Rev. Gen. 281. 1891. 
Shrubs, erect or prostrate, branched, the branches terete or angulate. Leaves opposite, 
crowded and usually densely imbricate, thick-coriaceous, small. Stipules entire, bifid, or 
setose. Inflorescence various, the flowers mostly solitary and axillary or cymose, usually 
small; hypanthium globose or turbinate; calyx 4-lobate (rarely 5-lobate), the lobes erect, 
remote; corolla funnelform or salverform, the tube short or elongate, glabrous or villous within, 
the limb 4-lobate, the lobes glabrous or pilose, valvate. Stamens 4, inserted in the corolla- 
throat; filaments short; anthers dorsifixed, oblong, included or exserted. Disk fleshy. Ovary 
2-celled; style filiform, shortly bilobate; ovules few, the placentae adnate to the septum. 
Capsule turbinate to globose, 2-celled, usually septicidally dehiscent to the base, few-seeded. 
Seeds oblong, concavo-convex, punctate; endosperm corneous; embryo clavate. 
Type species, Arcytophyllum blaerioides Willd. 
* Sometimes written Arcythophyllum. 
