The Fresh-Water Fauna of Central Europe ¹

Abstract

PROF. ZSCHOKKE'S (1) monograph, which is provided with three excellent maps, gives a detailed account of the present state of our knowledge of the composition, distribution, and biology of the deep-water fauna of the lakes of central Europe. For purposes of description the lakes are divided into sub-alpine and high-alpine series. Lake Lucerne is taken as a prototype of the former, and an account is given of its various basins and their deep-water organisms. One hundred and ninety-eight samples of the bottom, including some from the maximum depth (214 metres), have been taken, and have been examined by various workers. The bottom of this lake (and of other sub-alpine lakes) is coyered with fine mud, in which vegetable remains-fibres, leaves, pollen of conifers, &c.—are everywhere present, and in some places abundant. Among this material large numbers of Olieochæta, Nematoda, and insect-larvé thrive.