THE NETTLE FAMILY. 353 



and flat, tapering to each end, and in substance thick and leathery. 

 After this, it changes again, distending itself into a tubular cup, 

 deep, long, and wide enough to admit the finger ; and lastly, there is a 

 circular lid, the size of a sixpence, articulated to the edge of the cup 

 by a delicate hinge, like the cover of a hot- water jug, and shut down 

 close upon it, or lifted away, according to circumstances. This lid- 

 like appendage alone is the actual leaf; the lower portion, flat part 

 and pitcher included, being only petiole. The twisting and curling of 

 the latter at the base serves to keep the pitcher upright, and thus 

 prevent the watery fluid, with which it is usually half-filled, from 

 running out. The flowers, which are green and unattractive, grow iu 

 spikes about as long as the leaves. The pitcher- plant is not of very 

 common occurrence, but may be seen under the cupola of the conser- 

 vatory at the Botanic Gardens. 



CXI.— THE NETTLE FAMILY. Urticacea. 



The plants which compose the Nettle Family are very fairly repre- 

 sented in the unsightly and ill-natured weed from which it is named. 

 With the exception of a few tropical species, which attain the stature 

 of trees, they are low-growing and obscure, seldom above two or three 



Fig. 184. 

 Flower of Pellitory (magnified). 



feet high, usually covered either with stinging hairs or with asperities, 

 and bearing minute and unattractive green flowers. The leaves are 

 opposite or alternate, usually petiolate, simple or a little divided, 

 serrate or entire. The inflorescence is various ; the flowers, which 

 consist of calyx only, are tetramerous, and generally unisexual, the 

 males having four stamens, opposite the sepals, and the females a 

 solitary and superior ovary, containing a solitary and erect ovule. 

 The stigma is fringed, and usually sessile ; the fruit is a dry, flattened, 

 seed-like achenium, covered by the permanent calyx, and with the 

 embryo straight, and enclosed in fleshy albumen. It is this last 

 character that essentially distinguishes the Urticaceaj from the Che- 



25 



