LXXX. URTICACEvE. 
391 
Humulus.'] 
3. U. dioica L. ( great N.) ; leaves ovate acuminate or ovate- 
lanceolate serrate cordate or rounded at the base, spikes in 
pairs mostly dioecious much branched longer than the petiole, 
root perennial. E. B. t. 1750. 
Waste places under walls and hedge-banks, frequent. If. . 6 — 9. 
— When the leaves are broad they are cordate; when narrow, rounded 
at the base ; but transitions may be observed on the same specimen. 
Filaments transversely wrinkled and elastic as in Parietaria. Fertile 
perianth often with two small bracteas at the base. 
2. Parietaria Linn. Wall-Pellitory. 
Polygamous. Perianth 4-fid. Slam. 4, wanting in some 
flowers ;f laments transversely wrinkled, at first incurved, then 
bending back with elastic force. Style filiform. Stigma peni- 
cillate. Achene shining, enclosed by the perianth. — Leaves 
alternate. — Named from paries , a wall ; the species frequently 
growing on old walls. 
1. P. officinalis L. (common TP.) ; leaves oblong-ovate or ovate- 
lanceolate attenuate at both ends 3-nerved above the base, 
involucre of two 3 — 7-lobed segments with an alternating 
bractea 3 — 7-flowered, flowers sessile, that between the seg- 
ments with a pistil only, one only on each segment perfect at 
length enlarged tubular coloured and longer than the stamens, 
the others (when present) barren always short and campanu- 
late. — a. involucres mostly 3-flowered, stems ascending or 
diffuse. E. B. t. 879. P. ramillora Matnch. P. diffusa Koch. 
— id involucres mostly 7-flowered, stem usually erect. P. 
officinalis Spr. P. erecta Koch. 
Old walls and waste places among rubbish. — A. more rare. Essex ; 
Pembroke; North Wales. Stirling and Linlithgow. %. 6 — 9. — 
Stems reddish, pubescent. Flowers hairy, clustered in the axils of the 
leaves. The structure of the clusters in this genus we have explained 
fully in the 6th and 7th editions of this Flora, to which we refer ; 
and when correctly understood the difference between our two varieties 
ceases to be of specific importance. 
Sub-Ord. II. CANNABINE/E. Diceciovs. Barren fl. race- 
mose or panicled. Filaments of stamens straight and anthers 
erect during (estivation. Stigmas 2, sessile , filiform. Ovule 
pendulous. Embryo hooked or spiral, ivith a long radicle, 
without albumen. Stipules small. Juice watery. 
3. Humulus Linn. Hop. 
Barren fl. Perianth 5-partite. Siam. 5. Anthers with 2 
pores at the extremity. Fertile fl. in a catkin, the scales (pe- 
