I30 FLOWERS OF LAKES, RIVERS, ETC. 



RkinoJichiis inconspectus, and a 1 Imiioptcrous insect, Aplialani caltluc, 

 feed upon it. 



The second Latin name refers to its amphibious habitat. It is 

 called Arsmart, Flatter-dock, Willow Grass, (Ground Willow, Lake- 

 weed, Red Shank, Ruckles, Willow-weed. Ruckles was the name 

 given to a pond weed said to be dangerous to bathers by impedinL; 

 their swimming- — probably this one. The name Willow Grass is given 

 to the land form because the leaves resemble those of a willow. 



It is very difficult to eradicate from garden ground, in which it 

 sometimes occurs. 



E.SSENTIAL -Sl'KCIFIC Cr:.\RACTKRS : — 



268. Polygoititni anipIiibiHin, L. — Rootstock creeping, stem erect or 

 submerged, with floating leaves, aquatic form glabrous, terrestrial 

 hirsute, leaves oblong, cordate below, flowers pink, in terminal spikes, 

 solitary. 



Crack Willow (.Salix fragilis, L.) 



Though a marsh plant, there are no traces of this tree in ancient 

 deposits. It is found in the N. Temperate Zone in Europe, N. and 

 W. Asia, and has been introduced in N. America, but is said not to 

 be indigenous except in X.W. Asia. In Great Britain it is absent 

 In N. Devon, E. Kent, Bucks, E. Suffolk, Hunts, Monmouth, Pem- 

 broke, Cardigan, Flint, Derby, Mid Lanes, Isle of Man, Dumfries, 

 Kirkcudbright, I'ife, Mid Perth, N. Perth, N. Aljerdeen, Banff. W. 

 Highlands, except Clyde Islands, Cantire, N. Ebudes, N. Highlands, 

 North Lsles, but occurs elsewhere from Ross to the South coast. It 

 grows at 1^00 ft. in Northumberland. It is not native in Scotland 

 or Ireland or the Channel Islands. 



The occurrence of the Crack Willow in any localitv iiulicates moist, 

 damp ground, whether it be a marsh, the margin of a pool, pond, or 

 lake, or the side of a ditch, stream, or ri\'er. Where\'er it grows it is 

 a hygrophyte, loving moist conditions, and it is normally a lowland 

 plant. 



This tree may be recognized at a distance by its tall trunk, slightly 

 listing, with widely-spreading branches, incurved upwards, thus afford- 

 ing ample shelter in spite of its small leaves. The plant has the tree 

 habit. The tree is often 90 ft. in height, and in girth 10 tt. Th(> 

 branches spread obliqueK', ami are round, polished, smooth. The 

 twigs become easily broken (hence fragilis). They are yellowish- 

 brown. The leaves are lance -shaped to ellijnic. long and narrow - 

 pointed, hairless, glandular, toothed, bluish-green below or pale. The 



