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5. It should be clearly unlerstood, however, that Fig. 5 represents three successive stages in the inflow of the tip of a prominence, whereas in the cas illusrated in Fig. 4 the tip had already reached a point above the elee of th penumbra before the observations were begun. With a rather wile second slit, nearly the whole length of this curved flocculus (A to C) could be recorded in a single photogrsph, as shown in Fig. 3.