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Spring Flora of Oklahoma 
FAMILY 60. LOASACEiE. Loasa Family. 
Herbaceous plants, with either stinging or jointed and 
rough-barbed hairs, no stipules, calyx-tube adnate to a 
1-celled ovary, parietal placentae, and a single style. 
Stamens usually very numerous, some of the outer occa¬ 
sionally petaloid. Flowers perfect, often showy. 
I. MENTZELIA L. 
Erect herbs, mostly annuals, with alternate, entire, lobed 
or pinnatifid leaves, and terminal, solitary, or cymose flow¬ 
ers. Calyx-tube cylindric, linear or club-shaped. Petals 
5, spreading, deciduous. Stamens 20-100. Ovary 1-celled. 
Styles 3, more or less united. Capsule few-many-seeded. 
Seeds mostly prismatic, roughened or striate. 
1. Mentzelia oligosperma Nutt. Few-seeded Mentzelia. Rough 
ancl viscid-pubescent. Leaves ovate or oval, coarsely dentate or sin¬ 
uate. Flowers yellow, 5"-10" broad, axillary or somewhat cymose, 
opening in snshine. Capsule linear, 6"-8" long. Calyx lobes about 
3" long, persistent on the capsule. 
Prairies and plains. May-July. Oklahoma and Comanche coun¬ 
ties. 
FAMILY 61. LYTHARACEiE. Loosestrife Family. 
Herbs or shrubs, mostly with opposite leaves and solitary 
or clustered, mostly axillary, perfect flowers. Stipules 
usually none. Calyx persistent, free from the ovary and 
% 
capsule but inclosing it, the petals and definite stamens 
borne in its throat, a single style, and numerous small 
seeds on a central placenta. 
I. AMMANNIA (Houst.) L. 
Annual, glabrous or glabrate herbs, mostly with 4- 
angled stems, opposite, sessile, narrow leaves, and small, 
axillary, solitary or cymose flowers. Calyx campanulate, 
