The fisheries are important, principally those for shrimps and lobsters.
The shrimps and their allies are distinguished from the larger Macrura, such as the lobsters and crayfishes, by greater development of the paddle-like limbs of the abdomen or tail, which are used in swimming.
It is now known to consist of the young fry of herrings and sprats in varying proportions mixed with a few shrimps, gobies, sticklebacks, pope-fishes and young flounders: but these impurities are as far as possible picked out from the whitebait before it is marketed.
Shrimps (kawa-ebi) also are found in the rivers and rice-fields.
Shrimps, soles and flounders are taken in great numbers in the estuaries of the Thames and Medway, along the north coast and off Ramsgate.
The neighbouring Pegwell Bay, famed for its shrimps, is supposed to have been the scene of the landing of Hengist and Horsa, and at Cliff's End (Ebbs Fleet) a monolithic cross marks the landing-place of St Augustine in 596.
In the Zuider Zee small herring, flat fish, anchovies and shrimps are caught, the chief fishing centres being the islands of Texel, Urk and Wieringen, and the coast towns of Helder, Bunschoten, Huizen, Enkhuizen, Vollendam, Kampen, Harderwyk, Vollenhove.
The annual value of the shell-fish (lobsters, crabs, oysters, mussels, clams, periwinkles, cockles, shrimps) is about £73,000.
Shrimps, crabs and lobsters form an important source of food supply.
The middle one contains but two families, the cylindrical and often thread-like skeleton shrimps, Caprellidae, and their near cousins, the broad, flattened, so-called whale-lice, Cyamidae.
CRUSTACEA, a very large division of the animal kingdom, comprising the familiar crabs, lobsters, crayfish, shrimps and prawns, the sandhoppers and woodlice, the strangely modified barnacles and the minute water-fleas.
The Stenopidea, another primitive group, differing from the Penaeidea in the character of the gills,, appear in the Trias and Jurassic. The Caridea or true prawns and shrimps appear later, in the Upper Jurassic, some of them presenting primitive characteristics in the retention of swimming exopodites on the walking-legs.