Media type: E-Article Title: Die Holarktis Contributor: Just, Th.; Reinig, W. F. imprint: JSTOR, 1937 Published in: American Midland Naturalist Language: Not determined DOI: 10.2307/2420662 ISSN: 0003-0031 Keywords: Ecology, Evolution, Behavior and Systematics Origination: Footnote: