This section is from "The American Cyclopaedia", by George Ripley And Charles A. Dana. Also available from Amazon: The New American Cyclopędia. 16 volumes complete..
Sprat, a small fish of the herring family, and genus harengula (Val.). There are teeth 'on the jaws, tongue, palate, and pterygoid bones, but none on the vomer; the branchios-tegal rays are six or seven. There are about ten species, of which the most common is the English sprat (II. sprattus, Val.), called garvie in Scotland; it is 5 or 6 in. long, with the body proportionately deeper than in the herring, and the edge of the abdomen strongly serrated; the scales are large, round, and deciduous; the upper part of head and back dark blue, with green reflections, passing into silvery white on the gill covers, sides, and abdomen; dorsal and caudal dusky, other fins white. It is found on the coasts of Great Britain and Sweden; it ascends the rivers in large shoals in November, after the herrings have disappeared. Though smaller than the herring, it furnishes in winter an abundant, cheap, and wholesome food, and is generally eaten fresh. The fishery is prosecuted by drift or stationary nets, and with most success in dark and foggy nights.
Several species in the West Indian seas are called sardines.
 
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