. Bulletin of the Bureau of Fisheries. Fisheries; Fish culture. lO BULLETIN OF THE BUREAU OF FISHERIES. CHANGES IN DISTRIBUTION OF PIGMENT IN CHROMATOPHORES. Changes in the distribution of the pigment granules in chromatophores have been studied by many investigators in both invertebrate and vertebrate animals. Never- theless, the manner in which these changes are brought about remains a controverted question. Two theories prevail at present. According to the one, the chromatophores contract and expand in an ameboid manner. Among the supporters of this theory may be mentioned von Wittich (1854
. Bulletin of the Bureau of Fisheries. Fisheries; Fish culture. lO BULLETIN OF THE BUREAU OF FISHERIES. CHANGES IN DISTRIBUTION OF PIGMENT IN CHROMATOPHORES. Changes in the distribution of the pigment granules in chromatophores have been studied by many investigators in both invertebrate and vertebrate animals. Never- theless, the manner in which these changes are brought about remains a controverted question. Two theories prevail at present. According to the one, the chromatophores contract and expand in an ameboid manner. Among the supporters of this theory may be mentioned von Wittich (1854), Busch (1856), Leydig (1857, 1873), Hering and Hoyer (1869), Pouchet (1876), Halpern (1891), Ehrmaim (1892), Ficabli (1896), Verworn (1909), Froelich (1910), Holmes (1913), and Hooker (1912, 1914). According to the other theory, changes in the distribution of the pigment do not involve essential changes in the form of the chromatophore, but the pigment granules move through the protoplasm or in fixed canals in it. Among the supporters of this theory may be mentioned Briicke (1852), Harless (1854), Virchow (1854), Lister (1858), Solger (1889), Biedermann (1892), Zimmermann (1893), Keeble and Gamble (1905), Kahn and Lieben (1907), Winkler (1910), Degner (1912), Ballowitz (1893, 1912, 1913, 1914), Franz (1908, 1910), and Spaeth (1913). That it is quite impossible in fresh preparations of the skin or in living fishes to observe the limits of the processes radi- ating from the central area of a mature chromatophore except in its fully expanded Fig. 4.âCamera lucida drawings taken at approximately lo- j*i' ⢠â e ^ minute intervals of a pigment eeU in an embroyo of Condition IS the COmmoU experience of UOt a parva 40 hours after fertilization. The stippled areas show few obsCrVCrS. That individual chrOmatO- the distribution of the pigment. i_ i j /i â¢j_ c phores possess a more or less definite form and that this form is retained, i. e., the position of each radia
Size: 1835px × 1362px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectfisheries, bookyear19
