[132]. Loc. cit. p. 150.
[133]. Keeble and Gamble, Phil. Trans., Ser. B, cxcvi., 1904, p. 295. The chromatophores are also directly responsive to light, but the lasting adaptations to colour-backgrounds are brought about indirectly, the stimulus being transmitted through the eyes and nervous system. The influence of light may also affect the metabolism of the animal, the chromatophores being accompanied by a ramifying fatty tissue, which disappears if the animal is kept in the dark.
[134]. Challenger Reports, xxiv., 1881.
[135]. Borradaile’s useful paper on the classification of the Decapoda (Ann. Mag. Nat. Hist. (7), xix., 1907, p. 457) should be consulted for this and other Decapod groups. Also Alcock’s Cat. of the Indian Mus., “Decapod Crustacea.”
[136]. Giard and Bonnier, Compt. Rend. Soc. Biol. 1892.
[137]. Coutière, Fauna and Geogr. Maldive and Laccadive Archipelagos, ii., 1905, p. 852.
[138]. Keeble and Gamble, Phil. Trans. Ser. B., cxcvi., 1904, p. 295. In the young a constant and very simple chromatophore-system is present, but in the adult a barred, lined, or monochrome colour-pattern may be present, which is ultimately induced by the nature of the environment, and does not subsequently change. In other species of Hippolyte, and in Palaemon and Crangon, only one adult colour-pattern occurs. Thus H. varians, besides reacting to light by its chromatophores, possesses a permanent colour-pattern, which is also determined by environment.
[139]. Claus, Unt. z. Erforschung d. genealog. Grundlage d. Crustaceensystems. Vienna, 1876.
[140]. Milne Edwards and Bouvier, Ann. Sci. Nat. (7), xvi., 1894, p. 91.
[141]. Garstang, Quart. J. Micr. Sci. xl., 1897, p. 211.