Australian botanist, photographer and artist, born in Mecklenburg, Germany. He had arrived in Victoria in the 1850s.
Walter discovered and collected a new species of mint bush on Mount Ellery which was named in his honour as Prostanthera walteri by Victorian Government Botanist Ferdinand von Mueller in 1870. He had accompanied the Victorian geodetic survey team headed by Government Astronomer Robert L. J. Ellery which surveyed East Gippsland and the border with New South Wales from 1869 to 1871. He collected plants on behalf of Anatole von Hügel and was accompanied by missionary George Brown in exploring the Bismarck Archipelago in 1875. From the 1890s until his death in 1907, Walter was head of economic botany at the Technological Museum in Melbourne.