Collections at the upper Neosho station were more intensive than at any other station, especially in 1959. Rotenone was used in the summers of 1957, 1958 and 1959, to obtain large samples of the population in one section of the stream. In September, 1959, the shocker was used in other sections in order to estimate populations in particular pools and riffles, to measure variability in the fauna between areas having slightly different habitat, and to record movement of marked individuals in a short section of the stream.
Description of Study-areas
Two sections of the stream, each about one-half mile long (See p. 366), were studied. Additional description of particular areas is presented below. Area 1 and the pools in which rotenone was used are on the Bosch Farm approximately two miles upstream from the White Farm where Areas 2, 3, 4, 5, 6 and 7 are situated.
Area 1 has a length of 210 feet, an average width of four feet, and a maximum depth of two feet. The upper half is a swift, rubble riffle four inches in average depth; the lower half is one and one-half feet in average depth and has a slow current (Pl. 29, Fig. 1).
Area 3 has a length of 186 feet, an average width of 34 feet, and a maximum depth of two and one-half feet. This area includes a shallow riffle at both upstream and downstream ends of a pool 73 feet long and approximately one foot in average depth (Pl. 29, Fig. 2).
Area 5 has a length of 250 feet, an average width of 50 feet, and a maximum depth of two and one-half feet. This is a shallow, quiet pool over rubble and bedrock bottom except for a small area of mud bottom (backwater) above the point where a short riffle drains into this pool from Area 6 (Pl. 30, Fig. 1).
Area 6 has a length of 200 feet, an average width of 50 feet, and a maximum depth of one and one-half feet. This is a shallow, quiet pool over bedrock bottom, except for a small area of mud bottom at one side of the upper end of the pool. A short, steep, rubble-riffle is included in this area at the upstream end (Pl. 30, Fig. 2).
Areas 2, 4, and 7 resemble at least one of the areas described above but were sampled less intensively. Data from areas 2, 4, and 7 are included in discussion of the total fauna of the upper Neosho river but are excluded from the discussion of representative parts of that fauna.