Comparison of species composition of green algae occurring in chosen ponds in Łódź in the years 1952–1958 and 1996–1998. Fragmenta Floristica et Geobotanica Polonica 7: 333–342. Kraków. PL ISSN 1640–629X. ABSTRACT: In samples collected in six Łódź ponds the occurrence of 83 green algae taxa in 1952–1958 and 100 taxa in 1996–1998 was determined. The analysis of species composition enabled distinguishing in the research period nine dominant taxa. New taxa for the central Poland: Closterium praelongum Bréb. var. brevius (Nordst.) Krieg., Coenochloris ovalis Korš., Cosmarium subprotumidum Nordst., Eutetramorus fottii (Hind.) Kom., Micractinium bornhemiense (Conr.) Korš., Scenedesmus incrassatulus Bohl., S. serratus (Corda) Bohl., Selenastrum capricornutum Printz. and Tetrastrum triacanthum Korš. were found.