492 J URTICACEAE 
Sepals of the pistillate flowers united: calyx-tube invest- 
ing the achene. Tribe IV. BOEHMERIEAE. 
I. UREREAE 
Stigma subulate, not tufted: ovary and achene oblique. 1. URTICASTRUM. 
Stigma tufted: ovary and achene equilateral. 2. URTICA. 
II, PILEAE 
Sepals yn the pistillate pick nearly equal, all slightly broad- 
ened or hooded e 3. ADICEA. 
Sepals at the pistillate flowers very unequal, the larger one 
helmet-like, 4. PILEA. 
II. PARIETARIEAE 
Diffuse flimsy herbs with soft watery stems and leaves. D. PARIETARIA. 
IV. BOEHMERIEAE 
Flowers monoecious, in glomerules on branches: leaves opposite. | 6. BOEHMERIA. 
Flowers dioecious, in axillary or lateral compound clusters : 
leaves alternate. . RAMIUM. 
1. URTICASTRUM Fabr. Perennial herbs with stinging hairs. Leaves 
alternate: blades toothed. Pistillate flowers with a calyx of 5 sepals and an 
oblique ovary.—About 25 species mostly o 
tropical regions. 
1. U. divaricatum (L.) Kuntze. Stem 
2-12.dm. tall: leaf-blades ovate, ovate- 
orbicular, or elliptic, 5-20 em. long, long- 
petioled: panicles "'Sprea ading, the lower 
staminate, the upper ace taps ob- 
long, or broader in the pis wers: 
achene DE iren 3 mm. in eens 
exserted.— (W TTLE. CANADA-NETTLE. 
NETTLE-PATCH. )— Rich woods and bottoms, 
various provinces, Fla. to Kans., 
d N. S.—Sum. 
2. URTICA [Tourn.] L. Annual or perennial often coarse herbs with 
stinging hairs. Leaves opposite: blades toothed or incised-lobed.  Pistillate 
flowers with a calyx of 4 distinct sepals and an equilateral ovary.—About 30 
species of Wide geographic distribution. NETTLES. 
Annual: flower-clusters simple. 
Leaf- — incised-toothed, the upper ones but little re- 
duc . U. urens. 
Leaf- Dad crenate-dentate, the upper ones much reduced. 2. U. chamaedryoides. 
Perennial: flower-clusters compound. 
Stems it api ced bristly : Heus more than half the 
breadth of the leaf-blad 3. U. gracilis. 
Stems CR ns petioles less than half the breadth 
of the leaf-blades 4. U. dioica. 
1. U. urens L. Stem and branches 1—4 dm. tall: leaf-blades oval, elliptic, or 
ovate, 14 em. long, rounded or broadly cuneate at the base, incised, the teeth 
