FLOWERING PLANTS
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FLYING-FISH
Flowering Plants. A common name applied to the highest group of plants, now more commonly called seed-plants or spermatophytes, which see.
Flu'orspar'. A transparent or sub-translucent brittle mineral found either in crystalline or in massive form. Its chemical name is calcium fluoride CaF3. Its color may be blue, brown, greenish, yellow, white and rarely red, but it commonly is yellowish or blue. It is found in England, Norway, Kentucky, Arizona, Illinois and Colorado. It is the chief source of fluorine and of hydrofluoric acid which is used for etching glass. Fluorspar is used in fusing certain minerals, in iron-smelting and also, when colorless, for the manufacture of lenses.
Flute, a musical wind-instrument, consisting of a tapered tube, in which the sound is produced by blowing with compressed lips into a hole near the top or wider end, which is stopped with a cork. Six holes in the lower end, closed and opened by the fingers, serve to make the musical scale. Flutes are usually made in cocoa-wood, ebonite, silver and gold. The flute is greatly used in classical music; Bach, Haydn, Handel, Mozart, Beethoven and Mendelssohn all giving it a leading part in their works. It is one of the oldest wind-instruments, having been used by the ancient Egyptians.
Flux. A flux is a substance used to make the process of melting minerals more easy. The commonest fluxes are limestone and fluorspar. A white flux is a mixture of the nitrate and carbonate of sodium or sometimes of potassium. A black flux includes carbonate of potash to remove silica and charcoal to combine with the oxygen in a metallic ore. In pottery, boracic acid, red lead and sand
fenerally are the chief ingredients in the uxes. A flux acts by combining with the useless matter in the ore, forming a slag in which the metal is left as free as possible, so that none may be lost in the smelting.
Fly, a two-winged insect. The word is used in compounds, as may-fly, stone-fly, butterfly etc., but when used alone is correctly applied only to two-winged insects. They belong to a natural order called Dip-tera. In the broad sense the mosquito, gnat and midge are flies. The common house-fly is the best-known representative. The apple-worm is the larva of a fly. Other injurious plant-eaters are the onion-maggot and the Hessian fly. The sting of the gall-fly produces a gall on plants, in which the eggs are deposited and the larvae reared,, Bat-flies infest cattle. Flies are very prolific and breed rapidly. They are useful as scavengers, and some are agents in the cross-fertilization of plants; but they also are agents in carrying germs of disease. There
are about 200 species of gad-fly or horsefly in this country. They include the strong, large flies common on wooded roads, and smaller ones, sometimes known as deer-flies, yellowish or greenish in color, a pest, annoying to both man and beast. In summer the eggs are deposited on stems and leaves, the larvae live in earth or water. The common house-fly is found all over the world. Contrary to popular belief it does not bite, its mouth-parts not being fitted for piercing. The stable-fly, which closely resembles it, sometimes enters houses before rain and its bite is laid to the house-fly. The eggs of the latter are generally deposited in horse-manure, occasionally in decaying vegetables. They hatch in from six to eight hours into white maggots, which under favorable conditions reach full growth in four or five days. After five days of pupa stage the adult fly comes forth. In a single summer a dozen generations may appear, and when it is taken into account that one female lays an average of 120 eggs, the great numbers of the pest are readily understood.
Fly=Catchers, name of a group of perching birds, having the following characteristics: Size, small or medium; colors, dull; head large, sometimes crested; sedentary, solitary birds, never seen in flocks; not songsters, voices more or less pleasing; in obtaining food make a sudden dash after a winged insect then return to their perch; aggressive and fearless. The fly-catchers include the king-bird, wood-pewee, phoebe, Acadian flycatcher, great crested flycatcher, least flycatcher, olivesided flycatcher, yellow-bellied flycatcher and Say's flycatcher. See Blanshan: Bird Neighbors.
Flying=Fish, a fish capable of projecting itself from the water and sailing through
FLYING-FISH
the air. There are a number of fish, mostly in the warmer seas, that possess this power. They have large pectoral fins, that are spread as a parachute to sustain the body in the air, but are not used as wings. These fishes leave the water by the vigorous use of the tail-fin. They are rather small fishes, the largest species reaching a length
