1. 1) M. KONDO: Suido Kenkyu Shiryo (Osaka, Japan), No.19, pp. 308 (1933).
2. 2) AAP: Nat. Eutrophication Res. Program, Fed. Wat. Quality Adm., Pacific Northwest Water Lab., Corvallis, Oregon, 1971, pp. 1-82.
3. 3) G. L. HTTCHCOCK and T. J. SMAYDA: Limnol. Oceanogr., 22, 132-139 (1977).
4. 4) A. COLLIER, W. B. WILSON, and M. BORKOWSKI: J. Phycol., 5, 168-172 (1969).
5. 5) K. HIRAYAMA, S. IIZUKA, and T. YONEZI: Bull. Facuity Fish., Nagasaki Univ., NO. 33, 11-20 (1972).