The commonest species--the Round-leaved Sundew (_Drosera rotundifolia_)--is abundant and widely distributed, and may be seen among the bog-mosses, sometimes almost completely covering rather large patches of marshland. Its leaves are round, from a quarter of an inch to near half an inch in diameter, spreading in such a manner that they lie close to or near the ground. The flower-stems are slender, erect, from three to six inches long; and the white flowers, which are in a one-sided raceme, bloom during July and August. The Long-leaved Sundew (_D. longifolia_ or _D. intermedia_) has oval leaves, tapering gradually into the stalk. They are more erect than the leaves of the last species, and are not half so broad as they are long. The plant flowers at the same time as the latter, but is not nearly so common. The third species--the Great English Sundew (_D. anglica_)--is still rarer. Its leaves are still longer and narrower, being sometimes an inch or more in length, and more erect; and the flower-stalk sometimes attains a length of eight inches. The carnivorous habits of these plants are very similar to those of the Butterworts, but the movements connected with the capture of the prey are more marked in the red filaments which cover the upper surface of the leaves than in the leaves themselves. Those filaments which are situated on the margin of the leaf are longest, and spread outwards, while the others are erect and decrease in length from the edge towards the middle. Each filament is swollen at its extremity, and supports an enticing globule of glistening fluid which it secretes, for the enlarged extremity is really a minute gland. The fluid, though quite clear, is so viscid that it can be drawn out into threads, and it serves a purpose similar to that of the sticky globules on the spiral thread of a spider's web. If some grains of sand or other inorganic material be sprinkled on the leaf, the sticky secretion of the glands is appreciably increased, and at the same time assumes an acid character; but it contains no digestive ferment, nor do the filaments change their position to any considerable extent. When, however, a small insect alights on the leaf, attracted by the glistening drops which are probably mistaken for nectar, the secretion not only increases and becomes acid, but a digestive ferment is produced, and the little creature is soon besmeared with the fluid, its condition becoming more and more hopeless through its struggles, till at last further movements are impossible and it dies of suffocation.