In the list that follows, stations are numbered consecutively from the mouth of the Big Blue River, listing stations on each tributary as it is ascended. The letters following station-numbers indicate the general type of stream: S = sandy; M = muddy; and G = gravelly. The Big Blue River is the boundary between Riley and Pottawatomie counties, Kansas, along part of its length. Stations in this area have been designated Riley County. The legal description of each station is followed by the date(s) of collection, and each station is plotted in Figure 2. [Illustration: FIG. 2. Collection stations in the Big Blue River Basin, Kansas, 1957 and 1958.] [Illustration: PLATE 11 FIG. 1. Big Blue River at Station 3-S. U.S. Army Corps of Engineers photograph No. 563697. FIG. 2. Big Blue River at Oketo, Marshall County, Kansas. U.S. Army Corps of Engineers, photograph No. 67516.] [Illustration: PLATE 12 FIG. 1. Black Vermillion River, approximately one mile upstream from its mouth. Photograph by Robert G. Webb. FIG. 2. Carnahan Creek at Station 11-G. Photograph by Robert G. Webb.] 1-S: Pottawatomie Co., mouth of Big Blue River, Sec. 16, T. 10S, R. 8E, June 20, 1958. 2-S: Riley Co., Big Blue River, Sec. 4, T. 10S, R. 8E, June 6, 12, and 14, 1957. 3-S: Riley Co., Big Blue River, E 1/2, Sec. 30, T. 9S, R. 8E, Mar. 30, Apr. 6, July 15, 16, 17, Aug. 14, and Dec. 26, 1957; Apr. 26, June 20, and Aug. 5, 1958. 4-S: Riley Co., Big Blue River at Rocky Ford Dam, W 1/2, Sec. 30, T. 9S, R. 8E, Aug. 14, 1957; and Aug. 5, 1958. 5-G: Pottawatomie Co., McIntire Creek, Sec. 12, T. 9S, R. 7E, July 14, 1958. 6-S: Riley Co., Big Blue River and adjacent borrow-pit, Sec. 24, T. 9S, R. 7E, July 18 and 19, 1957; and July 11, 1958. 7-G: Riley Co., Tuttle Creek, Sec. 10, T. 9S, R. 7E, Aug. 5, 1958. 8-S: Riley Co., Big Blue River, Sec. 10, T. 9S, R. 7E, Aug. 14, 1957. 9-G: Riley Co., Mill Creek, Sec. 4, T. 9S, R. 7E, July 20 and 25, 1958. 10-G: Riley Co., Mill Creek, Sec. 2, T. 9S, R. 6E, Aug. 13, 1957. 11-G: Pottawatomie Co., Carnahan Creek, Sec. 22, 27, and 34, T. 8S, R. 7E, Aug. 1, 1957; and July 8, 1958. 12-G: Pottawatomie Co., unnamed tributary to Carnahan Creek, Sec. 15, T. 8S, R. 7E, Mar. 19, 1956 (collection made before my formal study was begun). 13-G: Pottawatomie Co., Carnahan Creek, Sec. 36, T. 7S, R. 7E, Aug. 13, 1957. 14-S: Riley Co., Big Blue River, Sec. 18, T. 8S, R. 7E, Mar. 22, 1958. 15-S: Riley Co., Big Blue River, Sec. 7, T. 8S, R. 7E, Apr. 3, and June 12, 1958. 16-G: Riley Co., unnamed creek, Sec. 1, T. 8S, R. 6E, July 10, and Aug. 5, 1958. 17-G: Riley Co., unnamed creek, Sec. 10, T. 8S, R. 6E, June 26, 1958. 18-G: Riley Co., Fancy Creek, Sec. 14, T. 7S, R. 6E, July 29, 1957. 19-G: Riley Co., Walnut Creek, Sec. 20, T. 7S, R. 6E, June 26, 1958.