. Experimental morphology. Protoplasm; Growth. 188 LIGHT AND PROTOPLASM [Ch. VII " ,,14:35 (4).,^ \- 14:31 d-. to 74: 142 14:20 to 14:34 S^ /Al:02 ' Fig. 53. — Camera drawing, showing the successive positions assumed by an amoeba subjected to light falling upon it from one side. The arrow lies in a horizontal projec- tion o£ the sun's rays. The amoeba retreats from the source of light. The numbers to the right of the outlines of the amoeba give the observed times between 10:28 and 11; Magnified 16 diameters. Fig. 54. — Camera drawing, showing the successive positions assumed by
. Experimental morphology. Protoplasm; Growth. 188 LIGHT AND PROTOPLASM [Ch. VII " ,,14:35 (4).,^ \- 14:31 d-. to 74: 142 14:20 to 14:34 S^ /Al:02 ' Fig. 53. — Camera drawing, showing the successive positions assumed by an amoeba subjected to light falling upon it from one side. The arrow lies in a horizontal projec- tion o£ the sun's rays. The amoeba retreats from the source of light. The numbers to the right of the outlines of the amoeba give the observed times between 10:28 and 11; Magnified 16 diameters. Fig. 54. — Camera drawing, showing the successive positions assumed by an amoeba retreating from the light. The position of the infalling ray was successively changed from (1) to (2), (3), and (4). The arrow labelled " First direction of migra- tion " shows the direction of loco- motion of the amoeba before the light fell upon it at the beginning of the experiment. The numbers indi- cate hours and minutes. Duringthe interval from 13;06 (=1:06) to 13:57, the amoeba was not under di- rect observation, since I was called S3 54 away. Magnified 16 diameters. Cases that can be explained only on the ground of the imme- diate effect of light upon the direction of movement are cer- tainly rare. Entz ('88), indeed, has intimated that Opalina flees from light, but Vbeworn ('89, pp. 53-57) was not able to confirm him in this point. Verworn's method was here, as in the case of Amoeba, not satisfactory. Instead of having the light fall from one side only upon the drop containing the Opalinas, he let the light pass vertically from below through a small hole, and could observe no tendency to avoid the illu-. 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 Davenport, Charles Benedict, 1866-1944. New York, The Macmillan company; London, Macmillan & co. , ltd.
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishernewyo, bookyear1897
