Reports study of Microcrustacea from 200 water bodies, collected during the summer of 1955. Twenty-two species of Cladocera, 29 Copepoda and six larger forms were identified. Some species characteristic of lakes or pools are separated. Surface temperatures ranged from 0.5 to 20.5 C. Chemical determinations of 48 water bodies include chloride, calcium, bicarbonate and oxygen. Similarities with Siberian and other high latitude forms are noted
