The Pigmentation of Cavernicolous Animals Iii. the Carotenoid Pigments of Some Amphipod Crustacea

INTRODUCTION During an investigation of the causes of pigment lack in cave Crustacea, it seemed desirable to study the kind of pigmentation in related above-ground (epigean) forms. The colour of three species of Isopoda was found to be due to a melanin-like pigment in branched cells (Baldwin & Beatty, 1941). Two plant carotenoid pigments— cryptoxanthine and /J-carotene—were present throughout the body tissues of one (Asellus aquaticus), but did not contribute significantly to the general colour of the animals. In the present work, it has been demonstrated that the colour of three species of Amphipoda is due wholly to carotenoid pigments, including in each case a proportion of a specific animal astacin-like pigment.