The relation of fishes to ions in their natural environments . r»»a-tlon experiments werer*»rfori>».1. T> r water flowed In at the Inlet In each end, was distri-buted y the brass tee (D, drifted slowly to the nlddle, diffusing ^rosaMTSwhat, and out through the outlets. On* fourth f 1 owed out through ;>of the two outlets at the tor and one *»lr:hth through each of the four atthe hotto™. The experir-ertiil i\x^tor was . per rain, rhis gave a Plowirto the tank, of 50 per mil., and the leai*-ed or-^:. Tapwater or water modified to a different degree flowed into the o
The relation of fishes to ions in their natural environments . r»»a-tlon experiments werer*»rfori>».1. T> r water flowed In at the Inlet In each end, was distri-buted y the brass tee (D, drifted slowly to the nlddle, diffusing ^rosaMTSwhat, and out through the outlets. On* fourth f 1 owed out through ;>of the two outlets at the tor and one *»lr:hth through each of the four atthe hotto™. The experir-ertiil i\x^tor was . per rain, rhis gave a Plowirto the tank, of 50 per mil., and the leai*-ed or-^:. Tapwater or water modified to a different degree flowed into the opr-orsit endat the san-e rate. Panplea for fating were withdrawr through ;3top-coc>(SCl or f-o- above by iearo of a pipette. Outlets . ,o.»itts. -re- times that desired in the treated w^ter end of the tank. The following variations of the simple grapMng method of record-ing, were used by Shelford and Allee and have been introduced here^CDjIn experiments where the fish was decidedly inactive and remained inone end of the tank, it was driven into the opposite end with a rubbertipped glass rod. The driving was done at regular intervals and wasrepeated at similar intervals in the controls, Dotted lines in thegraphs indicate that the fish was driven. Experiments of this sortwere few in number and have for the most part been thrown out. Insome experiments, however, the fishes were active and yet remainedconstantly in one end of the tank. Driving was again resorted to,in some cases, to make sure that the selection of the given end wasa reaction to the gradient. A return bo the original end would indicatethis to be the case. {&) A number of experiments w^*e -raa-de with 4-10small fishes in the tank at the same time. These experime
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfishes, bookyear1915
