Abstract

Myojin-ike is in the valley of Kamikoti, Nagano Prefecture, and is situated on the sea level of 1530 meters. The present investigation is based on the twenty collections of the fresh water algae made by the writer in summers of 1933 and 1936. They are carefully examined and 82 species and 15 varieties of algae are found. The yare : Cyanophyceae, 10 genera, 12 species ; Mastigophyceae, 2 genera, 2 species ; Chlorophyceae (exclusive of Conjugatae), 4 genera, 6 species ; Conjugatae, 13 genera, 26 species, 2 varieties ; Bacillariophyta, 17 genera, 36 species, 13 varieties.