. A biology of Crustacea. Crustacea. FEEDING, LOCOMOTION AND RESPIRATION T>5 small openings near the bases of the antennae. The position of this outflow is helpful in removing the products of the excretory organ, which opens on the base of the antenna. The surfaces of the gills are kept clean by the action of long processes (epipodites) extending backwards from the bases of the maxillipeds. These epipodites sweep over the gills and dislodge any particles which may have entered with the respiratory current. The current can also be reversed, so that water flows into the gill. Fig. 24. Polybiu
. A biology of Crustacea. Crustacea. FEEDING, LOCOMOTION AND RESPIRATION T>5 small openings near the bases of the antennae. The position of this outflow is helpful in removing the products of the excretory organ, which opens on the base of the antenna. The surfaces of the gills are kept clean by the action of long processes (epipodites) extending backwards from the bases of the maxillipeds. These epipodites sweep over the gills and dislodge any particles which may have entered with the respiratory current. The current can also be reversed, so that water flows into the gill. Fig. 24. Polybius henslowi (Decapoda, Brachyura), a swimming crab; note the large paddles at the ends of the last pair of legs. Although this crab is about the same size as the shore crab, Carcinus, its exoskeleton is much thinner and lighter. Actual width of carapace about 5 cm- chamber through the usual exit. This is a useful additional mechanism for clearing the gill chamber of foreign particles. Some crabs make regular use of the reversed current. The masked crab, Corystes cassivelaunus, lives in fine sand, and buries itself below the surface. The antennae are long, and each bears two rows of setae which overlap those of the other antenna and form a tube leading to the sand surface. By using the reverse respiratory current water is drawn down through this tube and is passed out through the openings at the bases of the legs. A similar modification is. 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
Size: 1611px × 1551px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodiversit, booksubjectcrustacea
