In other parts of the world it does not seem that the fresh-water Crayfishes are of much importance as an article of food. Some species of _Cambarus_ are so used to a limited extent in the United States, and the gigantic _Astacopsis serratus_ (Plate XX.) is known as the "Murray River Lobster" in the markets of Sydney and Melbourne. [Illustration: FIG. 78--THE COMMON SHRIMP (_Crangon vulgaris_). NATURAL SIZE] The Decapods of the suborder Natantia comprise a large number of edible species, generally known as Shrimps and Prawns. The Common Shrimp, _Crangon vulgaris_ (Fig. 78), which is plentiful on the British coasts wherever the bottom is sandy, is about two or three inches long, and when alive is of a translucent greyish colour speckled with brown. It differs from most of the Natantia in having the body somewhat flattened from above downwards, and the rostrum very short. When boiled, it is of a reddish-brown colour, and from this it is sometimes known as the "Brown Shrimp." On many parts of the coast the Shrimp fishery is of considerable importance. Most often the Shrimps are caught by means of a large bag-net attached to a semicircular hoop with a long handle, and pushed over the surface of the sand by a fisherman wading in the water at ebb-tide. A variety of species are sold in England under the name of Prawns. The largest of the native species, to which the name of Common Prawn is perhaps most properly restricted, is _Leander serratus_. It grows to a length of over 4 inches, and has a long serrated rostrum extending beyond the antennal scales and curving upwards at the point. The first and second pairs of legs end in small pincer-claws. When alive the animal is very transparent, and beautifully marked with bands of brown and red on the body and limbs. A smaller species of the same genus (_L. squilla_), distinguished by the much shorter and straighter rostrum, and another very similar species of which the proper name appears to be _L. adspersus_ (often known as _L. fabricii_), are said to be sold on some parts of the English coast as "Cup Shrimps."