a river of Central America, in Costa Rica, formed by the union of the Chirripo and Barbilla, flows eastward, and discharges itself into the Atlantic. The Matina flows smoothly over a bed unbroken by rocks, and is navigable during the whole of its course; as also are its tributary streams for some distance above their junction. The river is subject to annual inundations, which take place generally in December and January, though sometimes at earlier or later seasons, and which leave a deposit of thick and rich mud, to which the neighbouring country owes much of its fertility and the luxuriance of its vegetation. Ships can pass into this river from the port of Moín by means of a canal called the Baya.