This paper presents, in the first place, descriptions of ecological elements of the fishes in Lake Biwa, including spawning, habitat, feeding and growth and introductions of some other ecological works done in the lake. Secondly, by comparison of their ecologies, fish association and the food relations of them to other members of the lake are considered. Finally, these materials are discussed in relation to the current controversy concerning interspecific relations and coexistence of the fishes.
1.いままで日本では知られていなかつたDaphnia similis CLAUSが,大和郡山市内の溜池で発見された. 2.本種は従来D.carinataとして報告されていることが多く,上野益三博士は,アジア大陸に広く分布するD.carinataは,D.similisと改める必要があるといわれる. 3.本種は近年中国から,金魚の新しい品種を輸入した際に,魚とともに本邦に入り,それが増殖したものと推定される.