 Veitch selected Davis, and on 2 August 1873 he departed for South America.He remained in South America for three years, during which time he crossed the Andean Cordilleras in Peru, Colombia and Bolivia at least twenty times, at elevations of up to  and, like his predecessor Gustav Wallis he traversed the continent, travelling the entire length of the Amazon River.During his trip, he was successful not only in collecting "M. veitchiana" but several other species of the genus, including the graceful violet-blue "M. ionocharis" (which he found in the Andean valley of Sandia, in the province of Carabaya, Peru, at elevation) and the golden-yellow "M. davisii" (the Incas' "Qoriwaqanki" or "golden waqanki"), which Davis discovered in the vicinity of Cusco, Peru.