RIO DE LA PLATA, reo da is pl'a'ts. See PLATA, Rio DE LA.
RIO TtODORE, or THEODOR°, for merly known as Rio Dtrtrum (River of Doubt), a river of Brazil, rising in the Corde heira dos Parecis, in the western portion of Matto Grosso, flowing in a northerly direction from about the to the 5° of lat. S., and between the 59° and of long. W., and emptying into the Maderia, an affluent of the Amazon. It is the largest affluent of the Maderia, about equal in size to the Hudson, with many rapids and falls. Its length is nearly 1,000 miles. The lower course of the river had long been known to the rubbernaen, but the upper course, traversing. an unexplored portion of western Matto Grosso, was entirely unknown, and no part of the river was recorded on the maps. When the Roost, velt-Rondon expedition was starting on its exploring trip through southern and western Brazil in 1914 Colonel Roosevelt was ap proached by the Brazilian Minister of Foreign Affairs, Mr. Lauro Midler. Mr. Muller was
intensely interested in the development of the interior of Brazil, and asked Colonel Roosevelt to undertake the exploration of the Rio Duvida, of whose source or course nothing was known beyond its lower waters. The announcement of the exploration of a hitherto untraversed and unmapped river caused considerable comment and even doubt upon Colonel Roosevelt's re turn in the autumn of 1914, but he established the course and identity of the new river with out difficulty. It was at first christened Rio Roosevelt, but later was formerly designated as Rio Teodoro by the Brazilian government. Con sult Roosevelt, T., 'Through the Brazilian (1914).