_Area 3_ The order of abundance of the species at Area 3, in terms of the estimated population per 500 square feet, was as follows: red shiner (77.1), stoneroller (19.2), sucker-mouthed minnow (10.0), channel catfish (young-of-the-year) (8.1), sand shiner (5.8), channel catfish (yearlings and older) (3.1), long-eared sunfish (0.5), golden redhorse (0.4). Insufficient data make inclusion of other species unreliable. For comparison with the estimates of total population, the percentage-composition in the first collection gives the following results: red shiner (24.0%), stoneroller (17.4%), sucker-mouthed minnow (11.2%), channel catfish (yearlings and older) (7.6%), channel catfish (young-of-the-year) (7.0%), long-eared sunfish (6.0%), sand shiner (5.2%), and golden redhorse (1.0%). For the most part, the species have the same order of abundance in both methods of analysis. Those that are apparently out of order are channel catfish (yearlings and older) and long-eared sunfish. The first species is mobile (excepting young-of-the-year) and commonly fluctuates widely in numbers in the same area; the second species was treated differently in that only adults were considered in the population-estimation whereas both young and adults were considered in calculating percentage-composition. (I found that I could not confidently distinguish between young-of-the-year of green sunfish, long-eared sunfish and orange-spotted sunfish after staining.) _Area 6_ The order of abundance of the species at Area 6, in terms of the estimated population per 500 square feet, was as follows: red shiner (64.0), fat-headed minnow (41.5), blunt-nosed minnow (16.0), stoneroller (13.8), green sunfish (8.8), long-eared sunfish (1.9). Insufficient data make inclusion of other species unreliable. Calculations of percentage-composition give the following results: red shiner (20.1%), long-eared sunfish (14.6%), green sunfish (12.2%), fat-headed minnow (12.1%), blunt-nosed minnow (11.7%), stoneroller (5.8%). The two species of sunfish form a more significant part of the population in the latter analysis because young are included. Only adults were considered in the estimation of total population. The fact that estimates of the total population and the percentage-composition agree in most respects lends support to the validity of both methods of analysis. It should be re-emphasized that differences in the order of abundance in the various areas reflect the ability of each species to utilize each particular kind of habitat. Movement of Marked Fish TABLE 16. DATA ON MOVEMENT OF MARKED FISH AT THE UPPER NEOSHO STATION, SEPTEMBER, 1959.