. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 118 WILLIAM SCHALLEK was found not to be a controlling factor, since incandescent bulbs were substituted for fluorescent lamps without effect. Bulbs of 25, 60 and 300 watts were used without changing the normal behavior, showing that light intensity within this range is not a factor in migration (Fig. 4). An entirely different situation prevailed when the lamps were moved directly above the tank. Migration was now reversed, the animals mov- 20 40 CM FIG. 3. Arrangement of oblique and overhead lights. Distances in centimeters
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 118 WILLIAM SCHALLEK was found not to be a controlling factor, since incandescent bulbs were substituted for fluorescent lamps without effect. Bulbs of 25, 60 and 300 watts were used without changing the normal behavior, showing that light intensity within this range is not a factor in migration (Fig. 4). An entirely different situation prevailed when the lamps were moved directly above the tank. Migration was now reversed, the animals mov- 20 40 CM FIG. 3. Arrangement of oblique and overhead lights. Distances in OVERHEAD OBLIQUE 20202 TIME IN HOURS FIG. 4. Vertical distribution of A. toiisa in incandescent light. Top, lamps 60 cm. above tank; bottom, same, but 80 cm. to side. Ordinate, percentage of animals in top third of cylinders; abscissa, time in hours. ing up in the light and down in the dark (Fig. 4). If the overhead lights are kept on for 24 hours, the copepods stay up throughout this period, although animals in oblique light for 24 hours stay down (Fig. 5). The animals move up in overhead light, or in darkness following oblique light; they move down in oblique light, or in darkness following overhead light. The downward movement when the overhead light is turned off lasts for only an hour. After this time the normal upward movement in darkness begins (Fig. 6). This upward movement con-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laboratory
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
