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(1932). The Extent to which Temperature Changes Influence Food Consumption in Large-Mouth Bass (Huro Floridana) Transactions of the American Fisheries Society: Vol. 62, No. 1, pp. 202-210.

Pruthi's observations on the stickleback at pH 3.1 have been confirmed for the stickleback as well as several other species of fresh-water fish. Pruthi's criticism of the work of Powers is invalid within the pH range to which the fish are acclimated. The initial oxygen has either no effect on the lethal oxygen or the effect is in the opposite direction from that suggested by Pruthi. Outside of the pH range normal to the species in question the lethal oxygen is dependent in a large measure on the initial oxygen. Several species of freshwater fish--largemouth blackbass, smallmouth blackbass, white crappie, yellow perch, rainbow trout, as well as the goldfish and green sunfish--have the ability to extract oxygen from the water at low oxygen tensions equally well over a fairly wide range of hydrogen-ion concentration. The bluegill has a somewhat narrower range of toleration. The two species of minnow--steel-colored and bluntnose--tolerate a markedly narrower range of difference in hydrogen-ion concentration as shown by the lethal oxygen. The ability of fish to extract oxygen from the water at low pressure depends more or less on the hydrogen-ion concentration of water. The results obtained in this investigation confirm the studies on pH tolerancemore » of fish previously published. These results also confirm the observations that in highly alkaline water fish require a higher concentration of oxygen to survive.« less

(1962). Hatchery-Reared Atlantic Salmon Smolts in Ten Months. The Progressive Fish-Culturist: Vol. 24, No. 3, pp. 127-130.

1. A single collection of 369 specimens of the blunt nosed minnow, Hyborhynchus notatus, has been subjected to statistical study and microscopical examination for age determination. 2. The specimens were killed in April, before the opening of the breeding season, which other authors have shown to extend in central Illinois from May 1 to August 26. 3. The fishes measured in standard length from 1.3 cm to 7.9 cm. 4. The largest individuals are of the maximum size encountered in a collection of 6,440 specimens of the same species from the same county.5. Individuals under 4.5 cm are less than one year old with actual ages of from eight to eleven months. 6. In specimens over one year the males are regularly larger than the females: median for males 7 cm. for females 5 cm. 7. Oldest females are slightly under two years of age. Females seem to have a single breeding season and this in the second year. 8. Oldest males are slightly under three years. Only three-year males have pearl organs on the head, and some of...