Common bleak extracted from the scales of the common bleak, so-called "Essence Orientale" or "pearl essence", (used in making artificial pearls) which is crystalline guanine. Common bleak The common bleak ("Alburnus alburnus") is a small freshwater coarse fish of the cyprinid family. The body of the bleak is elongated and flat. The head is pointed and the relatively small mouth is turned upwards. The anal fin is long and has 18 to 23 fin rays. The lateral line is complete. The bleak has a shiny silvery colour; and the fins are pointed and colourless. The maximum length is approximately 25 cm. In
The Crab and the Fox their familiar pursuits and take up a business they know nothing about”. The fable appeared in the Medici manuscript in the 15th century and later among those recorded by Roger L'Estrange (1692). In Victorian times the story appeared in George Fyler Townsend’s new translation with the moral “Contentment with our lot is an element of happiness”. Crabs are not a natural food for foxes but anciently they were confused with crayfish and there is a freshwater species of crayfish that is eaten by foxes in the Balkan Danube region. There is in addition a South American Crab-eating Fox about which