Thirty-four scaled chrysophyte taxa are described from 17 Adirondack lakes located in either Hamilton or Franklin counties. Ten taxa, Synura sphagnicola, Syn. echinulata, Syn. petersenii, Mallomonas acaroides var. muskokana, M. hamata, M. caudata, M. crassisquama, M. galeiformis, Spiniferomonas trioralis, and Chrysosphaerella longispina, were found in more than 40% of the study lakes. Mallomonas acaroides var. muskokana, M. hamata, Syn. sphagnicola, Syn. echinulata, and Spiniferomonas coronacircumspina were common and important components of the phytoplankton floras in lakes with a pH < 5.4; however, M. hamata and Sp. coronacircumspina were noticeably absent from bog lakes. Synura sphagnicola and Syn. echinulata were as common in samples with a pH between 5.4 and 7 as they were below pH 5.4. Mallomonas crassisquama, M. caudata, M. pseudocoronata, and Synura spinosa were found in a significantly greater percentage of samples from circumneutral lakes and were lacking from waters with a pH < 5.4. Differences in species distributions between Hamilton County (higher mean pH) and Franklin County lakes further supported the observed pH ranges of the common taxa. Similarities and differences are made with a study of Smol et al. (Can. J. Bot. 62: 911–923), who described the distribution of scaled chrysophytes from the surface sediments of Adirondack lakes.