SPECIES AND VARIETIES. 31 1 



or stalked ovary, with two erect or recurved styles. — Shallow 

 waters or wet mud. Fl. May to September. 



(256) XJrtica. Nettle. 



U. Tirens : annual, with stiff, stinging hairs ; stems erect, 

 branching, ^-1 foot high, glabrous ; leaves ovate, deeply 

 toothed ; flowers in small, loose, almost sessile, axillary clus- 

 ters. — Cultivated and waste places. Fl. June to October. 



U. dioica: stems erect, 2-3 feet high, with copious stinging 

 bristles ; leaves cordate-ovate, coarsely-toothed ; flowers dioe- 

 cious, both males and females clustered in axillary, branched, 

 spreading spikes. — Hedges and waste places. Fl. July, Angust. 



(257) Parietaria. Pellitory. 



p. oflacinalis : stems branching, diff'use or procumbent, J-l 

 foot long, downy with short soft hairs ; leaves stalked, ovate 

 or oblong, entire ; flowers in sessile clusters. — Old walls, and 

 waste, stony places. Fl. July to September. 



(258) Humnlus. Hop. 



H. Lupulus : stems twining to a considerable height over 

 bushes and small trees ; leaves opposite, stalked, broadly 

 heart-shaped, deeply 3-5-lobed, sharply-toothed, rough but 

 not stinging ; flowers dioecious : the males in loose panicles in 

 the upper axils, small, yellowish-green ; the females in shortly 

 stalked, axillary, ovoid or globular spikes or heads, conspicuous 

 for their broad, closely-packed bracts, each with two sessile 

 flowers in its axil, the perianth a concave scale enclosing the 

 ovary ; scales of the spike becoming enlarged after flowering, 

 concealing the seed-like fruits. — Hedges, thickets, and open 

 woods. Fl. July. 



