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Sun-Dew

glands, tentacles, rod, plants, insect, ground and fly

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SUN-DEW, any herb of the genus Drosera, which is classified near the pitcher-plants and the roses. Several species are found in Amer ica. The flowers are very pretty, like that of the saxifrage, five-petaled, and borne at the top of a leafless scape, in a raceme, the buds in which are bent downward, the blossom of each day surmounting the arch and facing the sky. They are white or purplish in color. Sun dews grow in bogs or wet ground, the roots are poorly developed and yet the small plants thrive even in sphagnum; this is because they are flesh-eaters, and live on the nutriment ob tained from such insects as they can catch on their foliage; the roots, therefore, serving prin cipally to anchor the plants and to supply the large amount of water needed. The leaves, varying in shape in the several species, from round to filiform, are covered thickly on the upper face with wine-red filaments having a glistening drop like dew at the tips. These are stalked glands, destined for a purpose as deadly as that of the tentacles of the octopus. The leaf blades of the Drosera rotundifolsa, a com mon sun dew, are round, and are arranged in a rosette around the base of the flower-scape, the smooth green under surfaces resting on the ground. In times of inaction the tentacles ra diate in concentric circles and are tipped by their globular translucent glands, which sparkle with a viscid secretion exuded by them. But let a fly light on one of the glands and remain there, glued fast by the viscous fluid, and there is immediately a change in the state of things. In its efforts to release itself, the struggling insect is only besmeared more com pletely, chokes the organs of respiration and is ultimately smothered. In the meantime, the tentacles, disturbed by the fly, have become ex cited and have transmitted the stimulus to the other glands so that they all bend toward the tiny body, converging over it, and striving to touch it. They even shift the inert object toward the centre of the leaf-blade, so that the greatest number of tentacles may reach it. Such glands as succeed in touching the meat secrete an acid juice, with the addition of a ferment which is entirely similar to pepsin, and apply this secretion to the fly, digesting it, as it were. The glands then absorb the flesh and

blood of the meat, and also their own secre tions. The tentacles straighten up, the undi gested portions of the insect resting on the dry glands are blown away, and the glands soon begin to exude their viscid secretion again, and make themselves ready for a fresh victim. When a large insect is entangled, the leaf-blade itself folds inward slightly, so that a maximum number of tentacles may concentrate upon the food. D. Atomic has erect, very narrow leaves, and when an insect is caught by the glands, the leaves themselves bend toward it. In D. loagifolia the leaf-blade enfolds the fly. Sun-dew glands respond by bending to repeated touches, although no object rests upon them. It is only nitrogenous food which is obtained by this digestive process; carbonic. acid is as similated from the air as by other plants. Consult Darwin, C, Plants' (1875; new ed., 1900).

an hour-measuring instrument known from the earliest times to the Egyp tians, the Chaldxans and the Hebrews. It is worthy of remark, however, that no ancient Egyptian sun-dials have been found. Those connected with Egyptian remains have been recognized as all of Greek origin. The Greeks adopted it from their Eastern neighbors, and it was introduced into Rome during the First Punic War. One of the earliest types of sun dial found in Egypt, and still in use there, consists of a palm rod set upright in the ground, with a circular arc around it set out with stones to mark the hours as the shadow of the rod traverses the circle. Another more primitive form still in existence in Egypt has a rod laid horizontally in a north-and-south direction on two forked uprights, a short dis tance above the ground. At equal distances east and west of the rod are placed two stones or pegs. When the shadow of the rod lies across the westerly peg the day's work begins; when it reaches the easterly peg the day's work is ended.

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