28 NORTH AMERICAN FLORA [VOLUME 32 
tate; leaves opposite, sessile or nearly so, oblanceolate or linear-oblanceolate, 5-15 mm. long, 
2.5 mm. wide or narrower, obtuse or acute, usually hirsutulous on the costa above, glabrous 
beneath, ciliate near the base, l-nerved, the margins revolute; flowers axillary, the pedicels 
shorter than the calyx; hypanthium about 1 mm. long, hirtellous; calyx-lobes lance-oblong, 
acute; corolla salverform, 3 mm. long, white; capsule depressed-globose, subdidymous, 2-3 
mm. broad, about one fourth inferior, hirtellous; seeds cymbiform, rounded-oval, black, with 
a short hilar ridge. 
TYPE LOCALITY: San Diego, Duval County, Texas. 
DISTRIBUTION: Known only from the type locality. 
8. Houstonia parviflora Holz.; Greenman, Proc. Am. Acad. 32: 284. 
1897. 
Diffuse annual, much branched, the branches slender, 1-10 cm. long, glabrous or scaberu- 
lous, the internodes equaling or exceeding the leaves; stipules minute, naked; leaf-blades 
linear or oblanceolate-linear, 5-10 mm. long, 2 mm. wide or narrower, acute at the apex, 
attenuate at the base to a slender petiole half as-long as the blade or shorter, glabrous; flowers 
few or numerous, axillary, solitary, the slender pedicels 3-10 mm. long, erect or ascending; 
hypanthium less than 1 mm. long, glabrous; calyx-lobes linear-oblong, acute, twice as long as 
the hypanthium, in fruit longer than the capsule; corolla salverform, equaling or slightly 
exceeding the calyx-lobes, white, glabrous, the lobes shorter than the tube, obtuse; anthers 
included; capsule subdidymous, compressed, 2.5 mm. wide, about two thirds inferior; seeds 
crateriform, 0.8 mm. long, dark-brown, scrobiculate. 
TYPE LOCALITY: Round Rock, Texas. 
DISTRIBUTION: Southeastern Texas. 
9. Houstonia arenaria Rose, Contr. U. S. Nat. Herb. 1: 70. 1890. 
Erect or ascending annual, 1-4 dm. high, the stems simple or much branched below, the 
branches slender, ascending or spreading, more or less angulate, glabrous, the internodes 
longer or shorter than the leaves; stipules minute, scarious, laciniate; leaves sessile or nearly 
so, linear or lance-linear, 1-3.5 cm. long, 1-5 mm. wide, acute at the apex, attenuate at the 
base, thin, glabrous, paler beneath, l-nerved; flowers secund, in lax naked cymes, mostly 
sessile, the terminal ones often long-pedicellate; hypanthium less than 1 mm. long, glabrous; 
calyx-lobes oblong, obtuse, equaling or exceeding the hypanthium, in fruit much exceeding the 
capsule, the margins obscurely scaberulous; corolla funnelform, white, 3-5 mm. long, usually 
minutely puberulent outside, the lobes oblong, obtuse, half as long as the tube or longer, 
glabrous within; anthers exserted; capsule subglobose, somewhat narrowed at the base, 2—2.5 
mm. thick, costate, almost wholly inferior; seeds oblong, peltate, concavo-convex, minutely 
scrobiculate, dark-brown. 
TYPE LOCALITY: La Paz, Lower California. 
DISTRIBUTION: Southern Lower California. 
10. Houstonia Brandegeana Rose, Contr. U. S. Nat. Herb. 1: 70. 
1890. 
Erect or ascending annual, 1-2 dm. high, diffusely branched, the branches very slender, 
subangulate, glabrous or minutely hispidulo-puberulent, the internodes mostly longer than the 
leaves; stipules minute, scarious, laciniate; leaves sessile, linear or filiform, 5-8 mm. long, 
0.5 mm. wide, obtuse, thin, minutely puberulent on the upper surface, glabrous beneath; 
flowers axillary and in loose cymes, the pedicels filiform, 0.5-3 cm. long, spreading; hypan- 
thium less than 1 mm. long, glabrous; calyx-lobes oblong or oval, equaling or shorter than 
the hypanthium, in fruit exceeding the capsule; corolla funnelform, 4-6 mm. long, glabrous 
outside, purplish, the lobes oblong, obtuse, as long as the tube, glabrous within; anthers 
short-exserted; capsule broadly turbinate, 2 mm. long and nearly as broad, almost wholly 
inferior; seeds minute, oblong, concavo-convex, dark-brown. 
TYPE LOCALITY: La Paz, Lower California. 
DISTRIBUTION: Sandy plains, southern Lower California. 
