Oskar Schneider was one of the early collectors of reptiles in German South West Africa (now Namibia) during the eighteen-eighties. Specimens collected by him, H. Schinz*, E. Fleck* and others were described by O. Boettger between 1886 and 1894.
He was presumably the same person as O. Schneider who wrote a "Vorläufiger Bericht über einige sekundäre Mineralien von Otavi; darunter eine neues Cadmium Mineral" (Preliminary account of some secondary minerals from Otavi [German South West Africa], including a new Cadmium mineral), published in the Centralblatt für Mineralogie, Geologie und Palaeontologie (Stuttgart, 1906) a few years after his death.
Professor Doctor Oskar Schneider (1841-1903) also published (in German) a contribution on the Greek-orthodox church in Egypt (1874, 44p), a book on the beetles of the Caucasus (1878, with H. Leder), and Naturwissenschaftliche beiträge zur geographie und kulturgeschichte (Natural science contributions to geography and cultural history; Dresden, 1883, 276p), and was the editor of an atlas for schools (1881). Between 1865 and 1900 he furthermore wrote more than 30 papers on a variety of topics, mainly in geology, meteorology and zoology, and dealing with places such as Palestine, the island Elba, Illinois in the United States, the Caucasus, San Remo (Italy), and the island Borkum in the North Sea. The mollusc species Syndosmya schneideri was named after him.