. A biology of Crustacea. Crustacea. COLOURS 5' flat so that when pressed against the sand it does not cast a shadow. In this way the crab can apparently disappear. As a contrast to concealing coloration some Crustacea have strikingly conspicuous patterns which act as warnings to their predators. The best example is the African Land Crab, Sesarma meinerti, which has a purple back bordered with orange, and bright red chelae which it waves threateningly in the air. If caught away from cover this crab does not flee in the way that the Ghost Crab would, but stands its ground and will fight with co
. A biology of Crustacea. Crustacea. COLOURS 5' flat so that when pressed against the sand it does not cast a shadow. In this way the crab can apparently disappear. As a contrast to concealing coloration some Crustacea have strikingly conspicuous patterns which act as warnings to their predators. The best example is the African Land Crab, Sesarma meinerti, which has a purple back bordered with orange, and bright red chelae which it waves threateningly in the air. If caught away from cover this crab does not flee in the way that the Ghost Crab would, but stands its ground and will fight with considerable pugnacity. The contrasting pattern and conspicuous chelae adver- tise its powers of retaliation if attacked, and in fact it is rarely attacked. There are records of an allied species successfully defend- ing itself from the attacks of small dogs. The pattern of coloration often varies within a species, the Shore Crab Carcinus maenas is particularly variable when young; patches of green, yellow, white or red form a variety of patterns on the backs of crabs about an inch across, but when the crabs reach larger sizes they become more uniform in colour, with dark backs and paler undersides. One of the most striking examples of variation in pattern and colour within a species is found in the small shrimp Hippolyte varians. A number of variants, all captured on the same day at Brighton are illustrated in fig. 27. The young specimens in particular show great variation in pattern, and as a rule the pattern is effective in concealing the shrimp on a particular seaweed. If. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Green, J. (James), 1928-. Chicago, Quadrangle Books
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Keywords: ., bookcentury1900, bookcollectionbiodiversit, booksubjectcrustacea
