Young-of-the-year were taken at the lower Neosho station on 1 July, 1959 (and subsequently), in moderately fast water over gravel. On 21 August, 1958, a ripe female (eggs stripped easily) was the only slender-headed darter present in a collection from riffles at the middle Neosho station. #Percina caprodes# (Rafinesque) Logperch Logperch were not taken in the Marais des Cygnes. They were rare in the Neosho, where they were taken most frequently at the upper station in water two to three feet deep, over gravel bottom, in moderate to slight current. This species was present in intermittent pools at the upper Neosho station in 1957. #Percina copelandi# (Jordan) Channel Darter One specimen was taken at the lower Neosho station in 1959. Because no others ever have been found in the mainstream of the Neosho River, I suspect that my specimen is a "stray" from one of the smaller tributaries, where channel darters are locally common. #Etheostoma flabellare# Rafinesque Fan-tailed Darter The fan-tailed darter is represented in my collections by one specimen, obtained in the mainstream of the Neosho River at the lower station in 1957. Records of this species in Kansas are almost confined to the smallest, clear, permanent streams of the southeastern part of the state. My specimen may represent a small population that retreated to the mainstream of the Neosho during drought. #Etheostoma spectabile# (Agassiz) Orange-throated Darter Orange-throated darters were common at the upper Marais des Cygnes and upper Neosho stations in 1959, rare at the middle and lower Neosho stations, and absent from the middle and lower Marais des Cygnes stations. The species was found almost exclusively on upstream riffles over gravel-rubble bottom. The population in the upper Neosho was decimated by drought, and the fish did not become common until the summer of 1959, the third year after resumption of normal stream-flow. Deacon and Metcalf (1961:320) indicated that long periods of intermittency result in depletion or elimination of populations of the orange-throated darter in the Wakarusa River, Kansas. A limited number of orange-throated darters probably survived in the few permanent pools in the upper Neosho and provided the brood-stock necessary to repopulate this section of the stream. #Aplodinotus grunniens# Rafinesque Freshwater Drum