. Experimental morphology. Protoplasm; Growth. 76 SOLUTIONS AND PROTOPLASM [Ch. IH the whole form of the organism has been likened to a horse- chestnut with its shell on. (Kuhne, '64, pp. 48, 83; Czerny, '69, p. 159.) Zacharias ('84, p. 254, and '88) has described a similar phenomenon in the spermatozoon of Polyphemus pedicu- lus. When put into a 3% NaCl solution the spermatozoa lost their cylindrical form and protruded long pseudopodia. A remarkable fact about the pseudopodia, moreover, was that in locomotion they were used like flagella. Likewise, Fabre- DoMERGTJE ('88, p. 102) and Massart (
. Experimental morphology. Protoplasm; Growth. 76 SOLUTIONS AND PROTOPLASM [Ch. IH the whole form of the organism has been likened to a horse- chestnut with its shell on. (Kuhne, '64, pp. 48, 83; Czerny, '69, p. 159.) Zacharias ('84, p. 254, and '88) has described a similar phenomenon in the spermatozoon of Polyphemus pedicu- lus. When put into a 3% NaCl solution the spermatozoa lost their cylindrical form and protruded long pseudopodia. A remarkable fact about the pseudopodia, moreover, was that in locomotion they were used like flagella. Likewise, Fabre- DoMERGTJE ('88, p. 102) and Massart ('89) have observed that the protoplasm of encysted Ciliata swells or contracts according as it is placed in a less or more dense medium; the cyst thus being perfectly permeable by water. Massart has, indeed, obtained a rough quantitative expression of this state- ment, which is given in Tables X and XI, p. 87. Hambfe-. Fig. 9. — Blood corpuscles of the frog. 1, 2, normal; 3, 4, 5, various degrees of plasmolysls by solutions. a, nucleus and shrunken plasma; 6, water-filled spaces. (From Hamburger, '87.) GER ('87) has found that dense solutions produce the same modifications upon blood-corpuscles (see Fig. 9). Again, Grtjber ('89) has found those individuals of the heliozoon Actinophrys sol which live in fresh water different from those which live in the sea, and he has produced that dif- ference artificially. In the marine variety the plasm is dense, granular, free from vacuoles; while that of the fresh-water kind is extraordinarily rich in vacuoles, and has even a foamy appearance. If a marine form is gradually accustomed to fresli water its protoplasm soon acquires a vacuolated structure which renders it indistinguishable from the fresh-water one. Geuber also accustomed fresh-water Actinophrys to sea water, when it acquired the structure of the normal marine form. Likewise the marine Amoeba crystalligera, which has a dense protoplasm, becomes vacuolated after being accustome
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