Nests and/or nest-related behaviors are described for Micropterus dolomieui, Semotilus atromaculatus, Nocomis biguttatus, and Campostoma anomalum in a stream in eastern Oklahoma. Behavior of Notropis pilsbryi over a Semotilus atromaculatus nest is described, and commnents on reproductive behaviors in this and other species of the subgenus Luxilus (genus Notropis) are given. Until recently, information on the breeding habits of North American minnows has been provided primarily by the studies of a limited number of ichthyologists such as Hankinson, Reighard, Forbes and Richardson, Trautman, Hubbs, and Raney (see Miller, 1961, 1964 for citations). Most other contributors to this field have worked primarily with one or two species, and data from this group of authors is often secondary to other life history data and consequently less detailed, though there are numerous exceptions to this general statement, such as the studies of Marshall (1946), Pfeiffer (1955), Van Duzer (1939), Reed (1957), Outten (1957) and others. The majority of these studies, and particularly the most complete and detailed descriptions, have dealt with northern species primarily in New York, Michigan, Ohio, Illinois, and Pennsylvania. The breeding activities of minnows in other regions, the southwest and great plains in particular, are relatively poorly known. Although many streams in this region are too turbid to permit direct observation of behavior in nature, many streams along the western edge of the Ozarks in eastern Oklahoma are clear and include the western-most representatives of our Great Lakes trans-Mississippi fish fauna. Some observations on the behavior of various fish species have been made in some of these streams and clear lakes of eastern and southern Oklahoma by George A. Moore, Carl D. Riggs, and their students. The sparse nature of our knowledge of the breeding activities of cyprinid fishes in this area has prompted preparation of this paper, partly to encourage others to carry out investigations on these interesting fishes and partly to provide some data useful in comparing the behavior of local forms with their eastern cognates.