GOBY. The gobies (Gobizcs) are small fishes recognized by their ventral fins being united into one, forming a suctorial disc by which these fishes are enabled to attach themselves. They are essentially coastfishes, inhabiting nearly all seas but disappearing towards the Arctic and Antarctic Oceans. Many live in fresh waters, not far from the sea. Nearly 50o different kinds are known. The largest British species, Gobius capito, occurring in the rock pools of Cornwall, measures loin. None of the other British spe cies exceeds half this length. The Californian Gillichthys snirabilis, which is marine, is locally known as mudfish from its habit of mak ing excavations in the mud at low tide. The males are usually more brilliantly coloured than the females, and guard the eggs, which are quite frequently attached to a dead bivalve's shell or to a crab's carapace, with the convexity turned upwards and covered with sand.
Close allies of the gobies are the walking fish (Periophthalmus) of which various species are found in great numbers on tropical mud flats, skipping about by means of the muscular, scaly base of their pectoral fins, with the head raised and bearing a pair of pro jecting eyes close together.