The anchovy belongs to the same family of fishes as the herring, pilchard, and sprat, the family Clupeidæ. But whereas the herring, pilchard, and sprat have so many structural features in common that they are placed in a single genus, namely Clupea, the anchovy is in many respects so peculiar that it is placed in the distinct genus Engraulis. There are many species of Engraulis in various parts of the world, but only one on the coasts of Europe, and that one, commonly known as the ancovy, is called by zoologists Engraulis encrasicholus. The origin of these names dates back to a very early period. Both are used by ancient classical Greek authors.