424 THE ECOLOGY OP PLANTS, 



H. elodes is hairy, with stem-clasping rounded leaves, about an inch 

 diameter and woolly on both sides, firs, pale yellow 2 cms. diameter, 

 while H. quadrangulum has four-angled stem, 1-3 feet high, ovate 

 leaves, bright yellow flowers an inch across) ; Purple Loosestrife 

 (Lythrum salicaria, 2-5 feet, opp. lanceolate leaves, red-purple firs, in 

 spikes, heterostyled with three forms of flower) ; Water Purslane 

 (Peplis, a small annual rather like Montia, with opp. oblong leaves 

 2 cms. long, small white firs, in the leaf -axils, K 6, C minute or absent, 

 A 6 or 12 ; three species of Willow-herb (Epilobium, with epigynous 

 polypetalous flrs., parts in fours) Marsh W. (E. palustre, 1-2 feet, 

 leaves opp. sessile lanceolate, rose or lilac flrs. 4 mm. across), Square- 

 stemmed W. (E. tetragonum, like E. palustre but stem four-angled, 

 leaves serrate, flrs. 6-8 mm. across), Codlins-and-cream (E. hirsutum, 

 3-5 feet, leaves stem-clasping serrate 3-5 inches long, flrs. rose-purple 

 1-2 cms. across) ; Marestail (Hippuris, 1-2 feet, stem cylindrical 

 unbranched, leaves linear entire 2-6 cms. long in whorls of 6-10, flrs. 

 small, green in leaf-axils) ; several Umbellifers (Water Dropworts, 

 Water Parsnips, etc. ) ; Yellow Loosestrife ; Moneywort ; 

 Brook-weed; Bog-bean (Menyanthes, with stout rhizome, erect 

 shoots 6-10 inches, long-stalked leaves with 3 leaflets, white or pink 

 flrs. in raceme, K (5), (5) fringed inside with long white hairs, A 5, 

 G (2) with parietal placentation) ; Water Forget-me-not; Comfrey ; 

 Oipsywort ; Marsh Woundwort ; Skullcap ; Brooklime ; Water 

 and Marsh Speedwells ; Fig-wort ; Bed Battle ; Water Bed- 

 straws (Ocdium palustre and G. uliginosum, allied to Goosegrass, 

 Art. 233, both with square stems and small white flrs., the former 

 species has 4 or 5 "leaves" in a whorl, leaves oblong and blunt, flrs. 

 in large cymes, fruit smooth, while the latter has 6-8 parts in a whorl, 

 stiffer leaves with pointed tip, stem-angles more bristly, flrs. fewer in 

 cyme, fruit rough) ; Great Valerian ( Valeriana ojficinalis, stems 

 2-4 feet high, leaves opp. pinnate-compound with 9-21 lanceolate 

 serrate leaflets, pink flrs. in large cymes, K = feathery pappus, C (5) 

 bulged at base, A 3, G (3) with 1 ovule, fruit a composite -like akene) 

 and Small Valerian (V. dioica, 6- 18 inches high, leaves 5-7 cms. long, 

 lower ovate stalked, upper lobed, cyme much smaller, male firs, larger 

 than female) ; Water Ragwort ; Butterbur ; Hemp Agrimony ; 

 Marsh Cudweed ; Marsh Flume Thistle ; Yellow Fleabane. 



4O3. Moorland Vegetation. A moor is an elevated 

 tract of country consisting chiefly of peaty soil and inhabited 

 chiefly by Ling, Heaths, Bilberry, Cotton Sedge, and rough 

 or wiry Grasses. Low moors, or heaths, show much the 

 same kind of vegetation. 



High moors are widespread in Scotland and along the 

 Pennine range in England, occurring also in Wales and 

 Devonshire (Dartmoor and Exmoor). The underlying rock 

 is generally granite, sandstone, or shale, and between this 



