582 RUBIACEAE 
each other. Ovary 1- to 10-celled, the cells containing from 1 to 
several seeds. Fruit a capsule, a berry or a drupe. 
Shrub with flowers in a dense round head . . Cephalanthus 
Herbs, with opposite leaves or leaves in whorls of 3. 
Flowers in pairs, fruit a red berry . . . . Mitchella 
Flowers separate. 
2 carpels each one-seeded . . . . . . ~~ Diodia 
2 carpels each many seeded. 
Corolla funnel-form . .* . . . Houstonia 
Corolla wheel-shaped . . . . . Oldenlandia 
Herbs with leaves in whorls of 4 or more. 
Corolla commonly 4-lobed, flat, round . . Galium 
Corolla funnel-form. 
Flowers in heads surrounded by involucre leaves 
Or “eases: 2. ee Sh ee 
Flowers in loose clusters . . . . Asperula 
1. HOUSTONIA, L. 
Small, delicate herbs (with us), with opposite leaves and often with 
a rosette of leaves at the base. Stipules united with the leaf-stem. Calyx 
tube egg-shaped, 4-parted. Corolla tube slender, the 4 lobes spreading. 
Stamens 4, equal, inserted in the tube of the corolla. Ovary 2-celled, 
seeds numerous. 
1. H. coerulea, L. (Fig. 4, pl. 150.) Brvets. Innocence. Small 
herb, growing in tufts; stem 3 to 6 in. high, sparingly branched. Leaves 
oblong, spatula-form, opposite, forming a rosette at base, about 1/3 in. 
long. Corolla light blue, lilac or nearly white with a yellowish center. 
Tube longer than the lobes. Grassy places, our area. April-July. 
Var. Toronorum, Pease and Moore. Corolla white with yellowish cen- 
ter, tube shorter. White Mountains. 
2. H. longifolia, Gaertn. (Fig. 5, pl. 150.) LoNnG-LEAvep Hovs- 
TONIA. Tufted, stems 5 to 10 in. high. Basal leaves spatula-form, stem 
leaves linear. Flowers pale blue, purple to nearly white. Open dry 
places, throughout our region. May-Sept. 
3. H. ciliolata, Torr. (Fig. 6, pl. 150.) Frrncep Houstonta. Plant 
4 to 7 in. high. Stem leaves spatula-formed, lower leaves in a rosette, 
oval or pear-shaped, their margins fringed with hairs. Western New 
York, and southward. May-Sept. 
2. OLDENLANDIA, L. 
Slender herbs, erect or diffuse with opposite leaves, the small stipules 
united to the leaf stems and (in our area) small axillary flowers, white 
or pink. Calyx and corolla, each 4-parted. Stamens 4, equal, inserted 
in the throat of the corolla. Ovary 2-celled, ovules numerous in each 
cavity. 
