proper, with a smaller, unsymmetrical mouth and the ventral fins symmetrical or almost so; and (3) Psettinæ, the turbots (q.v.), having a large mouth and the ventral fins unsymmetrical.
The distinctions outlined above are not, however, very closely followed in common speech, where several species belonging technically to the first subfamily are popularly called ‘flounders.’ Thus the most important species of the coast of the Northern States is the summer flounder (Paralichthys dentatus), also called plaice, or deep-sea flounder, which may reach a length of three feet and a weight of 15 pounds, but usually is much smaller. Like the others, it is carnivorous, feeding on shrimps, crabs, small fish (which it often pursues rapidly at the surface), and even on carrion. It is most abundant on the shallow, sandy bottoms around Long Island, N. Y., where it is taken between May and October in vast quantities. Another very similar species replaces this on the southern coast, and still another in the Gulf of Mexico. The four-spotted flounder (Paralichthys oblongus), which has four oblong blackish spots, frequently comes to market. The ‘common’ or winter flounder (Pseudopleuronectes Americanus) is also valuable as a food-fish, and is the principal one caught north of Cape Cod; it is small and of excellent flavor, and is taken in late fall and early spring, when it approaches the shore to spawn. The best-known species of the Pacific Coast is the diamond flounder (Hysopsetta guttulata), brown blotched with bluish, and constantly caught for market. Several species are among the food-fishes of Alaskan waters, even along its Arctic coast. The pole flounder is a species (Glyptocephalus cynoglossus) of a group known as ‘flukes,’ and in England, where it is common and highly prized, it is called ‘craig fluke.’ It has been taken in great numbers by the beam-trawl off the coast of Massachusetts, and is regarded as nearly equal in flavor to the English or true sole.
Consult Goode, Fishery Industries, Sec. 1. (Washington, 1884). See Factors of Organic Evolution in the article Evolution. See Plate of Flatfish and Flounders.
FLOUR (formerly a variant of flower, q.v., for etymology). The ground and bolted substance of wheat. The name is also applied to other grains when ground, as rye flour, buckwheat flour; but if the grain from which the flour is made is not specified, the unqualified term, both in common and commercial usage, means wheat flour. The comparative importance of its production is shown from the fact that of the total cereal products milled in the United States in 1900, 62 per cent. were from wheat. Corn-meal, of which 13 per cent. of the total product consisted, ranked next, the remaining 25 per cent. being divided among the other cereals. That the use of wheat flour to the exclusion of all the other grains is not due to its higher nutritive qualities is shown from the accompanying analysis:
| CONSTITUENTS | Winter wheat |
Spring wheat |
Long-eared barley |
English oats |
Maize | Rye | Carolina rice |
| Fat | 1.48 | 1.56 | 1.03 | 5.14 | 3.58 | 1.43 | 0.19 |
| Starch | 63.71 | 65.86 | 63.51 | 49.78 | 64.66 | 61.87 | 77.66 |
| Sugar | 2.57 | 2.24 | 1.34 | 2.36 | 1.94 | 4.30 | 0.38 |
| Albumen | 10.70 | 7.19 | 8.18 | 10.62 | 9.67 | 9.78 | 7.94 |
| Nitrogenous matter | 4.83 | 4.40 | 3.28 | 4.05 | 4.60 | 5.09 | 1.40 |
| Cellulose | 3.03 | 2.93 | 7.28 | 13.53 | 1.86 | 3.23 | Traces |
| Mineral matter | 1.60 | 1.74 | 2.32 | 2.66 | 1.35 | 1.85 | 0.28 |
| Moisture | 12.08 | 14.08 | 13.06 | 11.86 | 12.34 | 12.45 | 12.15 |
As pointed out in the article Bread, the universal use of wheat flour for bread is due to the presence in the kernel of crude gluten, containing gliadin, a highly tenacious body, which is not present in the same form in other cereal flours. This adhesive or sticky quality of wheat flour enables it to retain the carbonic-acid gas inserted in the form of yeast or baking-powder, and thus produces ‘lightness’ in the bread. For the same reason other flours are used most successfully when combined with wheat flour. In fact, the other flours are rarely used alone for bread, except rye flour, from which the ‘black bread’ of Germany and northern Europe is made. This is a dark-colored, heavy, and sourish bread, very slow to dry, which is itself improved by combining wheat with the rye flour.
Historical Development of Milling Processes. Long before the dawn of history cereals formed an important article of food for the human race, especially for that portion of it inhabiting temperate climates. At first these grains were used in the wild state, without grinding or cooking. But agriculture was one of the earliest arts of civilization to be developed, and the cereals the first of the agricultural products to receive cultivation. It must have been discovered very early that both in ease of mastication and in flavor grain is much improved by grinding, so that the first milling processes came soon after the cultivation of the soil. At first a mere breaking up into coarse fragments by means of a mortar and pestle, or its substitute, was all that was attempted. This primitive form of milling, whose adoption constituted the first step in the art, still survives among certain peoples of rude civilization. The second step in the development of milling processes was taken when for the mortar and pestle were substituted two roughened grinding surfaces, placed close together, between which the grain was reduced to powder. This use of the upper and nether millstone for grinding grain also dates back to prehistoric times. An improvement over this simple device is the quern, or hand-mill, still used among semi-civilized peoples. In the quern the upper stone is pierced and turned on a pin on the nether stone; the upper stone is grasped by a handle consisting of a stick thrust into its edge. The use of animal and then of water power to turn the millstones came much later. The first successful steam flour-mill was erected in London in 1784. The use of millstones for grinding flour was universal until the close of the eighteenth
