URTICIFLORJE. 353 



internal leaves generally much larger and enveloping the fruit (340 B) ; it 

 often happens that all the perianth-leaves are united to form a gainophyllous 

 envelope. -flowers may occur among the others. THE INFLORESCENCES among 

 our native species are dichasii, which become transformed into unilateral 

 scorpioid cymes by the development of the bud of the 2nd bracteole. In 

 Parietaria they are more pressed together, and the floral-leaves at the same 

 time are also raised on their axillary shoots to just beneath the flower. As a 

 rule, not only in this order but also in those related to it, a small vegetative 

 branch is situated in the axil of the foliage-leaf, and this bears an inflorescence 

 on each side at its base. 



Urtica (Nettle) has opposite leaves with distinct stipules and 

 stinging hairs. The perianth-leaves of the ? -flower are free 

 (Pig. 340). -Parietaria (Pellitory) has scattered leaves without 

 large stipules, and stinging hairs are absent. The ? -perianth is 

 4-toothed, flask- or bell-shaped. Pilea is a tropical genus with trimer- 

 ous, zygomorphic ? -flowers, the posterior perianth-leaf being much larger than 



FIG. 310. Diagram of 3- and ? FIG. 311. Parietaria dijf'usa; hermaphrodite 



flowers of Uriica dioica. flower : a in the female, b at the commence- 



ment of the male stage ; the stigma lias fallen 

 off, but the anthers have not yet dehisced. 



the two others, and more or less hood shaped. The flower of Forskohlea is the 

 most reduced; the $ -flower has only one stamen, and the ? - as well as the $ - 

 flowers have a one-sided, tongue like perianth (?). Pouzolzla. 



WIND-POLLINATED. The pollen is shot out of the anthers, when they spring 

 forward, and is caught by long stigmatic hairs. Parietaria diffasa is protogy- 

 nous (Fig. 341). 



500 species ; chiefly in the Tropics, although the few species which occur 

 in Europe are represented by a much larger number of individuals. USFS. 

 The bast of the native species Urtica dioica and urens, of U. canuabina 

 (Siberia), etc.; of Boehmeria nicea "Ramie" and " China-grass" (from Sunda 

 Is., China), and others, is used in the manufacture of muslin. 



Order 3. Moraceae, (Mulberries). Nearly all trees or 

 shrubs, seldom herbs, generally with latex. The leaves are scat- 

 tered, and not infrequently lobed. The flowers are unisexual 

 (monoecious or dioecious) and arranged in catkin- or capitulum-like, 

 compound inflorescences. Perianth-leaves 2-6, generally 4, with an 

 equal number of stamens opposite to them, as in the Nettles. The 



w. B. A A 



