Five species of the genus Paspalum L., a southern genus in the Tribe Paniceae, range as far north as Kansas. These five show varying intergradation of characters which make them hard to identify. During the summer of 1965 population collections of Paspalum were made in Kansas. These, in addition to herbarium specimens, were studied in an attempt to establish constancies in variation that might aid in identification and to clarify the existing taxa of Paspalum in Kansas and their distribution in the state. As a result the following taxa of Paspalum have been designated for Kansas: P. fluitans (Ell.) Kunth, P. pubiflorum Rupr. var. glabrum Vasey, P. ciliatifolium Michx. vars. stramineum (Nash) Fern. and muhlenbergii (Nash) Fern., P. laeve Michx. vars. circulare Stone and pilosum Scribn., and P. floridanum Michx. vars. floridanum and glabratum Engelm. A key separating the taxa, descriptions, habitats, ranges, Kansas distribution, representative specimens, discussions, photographs, and distribution maps are given. Trans. Kans. Acad. Sci., 76 (2), 1973.