Urtica. | LXXI. URTICACE. 399 
Erect herbs. Leaves opposite ‘ ‘ F . . - URrIca 
Erect or procumbent herb. Leaves alter nate F , ; ; . 2. PARIETARIA. 
Tall twiner. Leaves opposite. E , . 3& HUMULUS, 
Among exotic genera in obnerAtibd may ie mentioned the Hemp 
(Cannabis), which, although an erect herb, is in many respects allied to 
the Hop; the Fig (Ficus), in which the flowers are collected in great 
numbers withinside a succulent receptacle, popularly called the fruit ; 
and the Mulberry (Morus), in which the flowers are collected in heads on 
the outside of a receptacle, and become succulent as the fruit ripens. 
I. URTICA. NETTLE. 
Erect herbs, with stinging hairs and opposite leaves. Flowers in 
axillary clusters or spikes; the males with a perianth of 4 segments 
and 4 stamens; the females with a perianth of 2 segments, or, if 4, the 
2 inner ones larger. Fruit a flattened seed-like nut, enclosed in the 
perianth. Stigma single, sessile, and tufted. 
A considerable genus, generally distributed over the globe. 
Annual and moneecious. Flowers in nearly sessile short clusters. 1. U. wrens. 
Annual and moneecious. Male flowers in loose spikes. Females 
in stalked, globular heads . ; ; : : : : . 2.0. pilulfera: 
Perennial, usually dicecious. Flowers in branched spikes. son US COWE. 
1. U. urens, Linn. (fig. 903). Smal’ N.—An erect, branching annual, 
seldom above a fost high and often only a few inches, glabrous" with the 
exception of the stiff, stinging hairs. Leaves ovate or elliptical, deeply 
and regularly toothed, more tender than in the two other species. 
Flowers male and female intermixed, in small, loose, almost sessile 
axillary clusters, 
In cultivated and waste places, especially in rich soils, throughout 
Kurope and temperate Asia, and carried out as weed of cultivation to 
other parts of the world. Common in Britain. FV. the whole season. 
2. U. pilulifera, Linn. (fig. 904). Roman N.—An annual like the 
last, but coarser and taller, attaining 2 feet, and very stinging. Leaves 
ovate or heart-shaped, deeply and regularly toothed. Male flowers in 
little, distinct clusters, along peduncles often as long as the leaves; the 
females in globular heads, on the summit of a peduncle from 4 to 1 inch 
long. When in fruit these heads are 4 or 5 lines in diameter, and 
thickly beset with stinging bristles. 
On roadsides, and in waste places, in southern Europe. Farther 
north only as an introduced weed in the neighbourhood of habitations, 
and as such occurs occasionally in the east of England. Fl. summer and 
autumn. U. Dodarti, Linn., is a variety with nearly entire leaves. 
_ 3. U. dioica, Linn. (fig. 905). Common N.—Rootstock perennial and 
creeping. Stems erect, 2 or 3 feet high, the whole plant of a-dark 
green, and more or less downy, besides the copious stinging bristles. 
Lower leaves cordate-ovate, the upper ones more or less lanceolate, 
narrowed at the point, coarsely toothed. Flowers usually dicecious, 
both the males and females clustered in axillary, branched, spreading 
spikes, usually about the length of the leaves. 
Along hedges, on roadsides, and in waste places throughout Europe 
and Russian Asia, from the Mediterranean to the Arctic regions, and 
carried out as a weed to other parts of the globe. Common in Britain. 
Fl. summer and autumn. 
