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The metabolism during starvation of Balanus balanoides
Oceanographic Abstracts
657
surface depression or cavity to the stagnation pressure based on the centre-line v~ocity of the jet in the neighbourhood of the surface. The second, a displaced-liquid analysis, related the weight of the liquid displaced from the cavity to the nomentum of the jet. Numerous experiments were conducted in which the cavity depth, diameter or width, and peripheral lip height were measured. The role of surface tension in affecting the cavity depth was considered and the phenomenon of drop formation was examined. Some attention was given to the case of a plane jet impinging on a moving liquid. It was found that the experimental data fit into the framework of these analyses quite consistently. BARAHONAFERNAD~ J. A., 1962. The use of Raydist in the survey of a bank offshore Lourenco Marques. Int. Hydrogr. Rev., Suppl., 3: 7-13. The example shown is typical of a very accurate offshore hydrographic survey, only possible with modern methods of radio navigation, and represents an interesting contribution to the better knowledge of the Mozambique Channel. Furthermore, the use of Raydist on the hydrographic ship, Almirante Lacerda has provided, as a result of the normal soundings, a large numher of current observations through the comparison of dead reckoning and Raydist positions. They show, at this stage, the very complex structure of the circulation in the Mozambique Channel, near L o u r e n ~ Marqu6s, with a main S.W. current offshore, a nearshore N.E. counter-current and several eddies in betw~n. B~att,rEs H., M. B~N~s and D. M. FnqLAYSOS, 1963. The seasonal changes in body weight, biochemical composition, and oxygen uptake of two common Borco-Arctic cirriped~, Ba/anus balanoides and B. balanus. J. Mar. Biol. Ass., U.K., 43 (1): 185-211. The seasonal changes in the body weight and composition of two common boreo-arctic species of cirripedes, Balanus balanoides and B. balanus have been followed. At a constant size (age under constant growth conditions) the body weight is closely related to the season. Increase in body weight takes place rapidly during the spring as reserves arc laid down. These reserves arc subsequently utilized for gonadal development. The changes in B. balanus are more gradual than in B. balanoides and piobably reflect differences in the habitat conditions. The reserves, although contributing to the gonads, are not themselves adequate for their total tissue. On copulation, body weight is grossly reduced and there is an uptake of water which is replaced when moulting is resumed after the reproductive anecdysis. The total changes in weight during growth are examined. Carbohydrate, fats, and proteins, are stored : the relative changes in these with season are examined. The seasonal changes in oxygen uptake of isolated whole bodies are related to the changes in comvosition and activity of the tissue. BAgN~ H., M. BAgNF.S and D. M. FXNLAYSON,1963. The metabolism during starvation of Balanus balanoides. J. Mar. Biol. Ass., U.K., 43 (1): 213-223. Changes in weight and biochemical composition of Balanus balancides when starved have been determined on summer and autumn animals. When there are considerable carbohydrate reserves these are first utilized, but, after they have fallen to about 10 per cent of the body weight, protein and lipid are used as metabolic substratvs. When carbohydrate reserves are present in quantity the moulting frequency is proportional to the amount present. In animals without carbohydrate reserves, protein and lipid are used immediately food is withheld. The drain ofexoskeleton formation on metabolism is relatively small compared with that in many other crustaceans. Protein and lipid can both provide the glucose necessary for chitin formation in a starved animal. The temperature coefficient of moulting frequency depends upon the substrate used; with the carbohydrate the Q~0 value approximates to 2-0, but when protein and lipid are being used it approaches unity. There is some reduction in oxygen uptake of isolated bodies on starvation when carbohydrate is being utilized. There is a gross discrepancy hetwven the oxygen demand as measured in isolated bodies and the available substrate; respiration is probably reduced during inanition. It is suggested that the moulting cycle is coupled to the metabolic activity in an obligatory fashion rather than being dominated by the kind of hormonal control found in decapods. BASCOMn C. L. and D. T. PglTC,ARV, 1963. A Cartesian hydrometer and its application t o sedimentation analysis. J. Sci. Inst., 40 (1): 30-31. The hydrometer described is particularly suited to sedimentation analysis. It consists of a Perspex framework covered by a thin rubber diaphragm. Manometer readings obtained axe sensitive to 0.00015 specific gravity units and the hydrometer can be adjusted to cover various ranges. Results for particle size analysis of six soils show better agreement with the standard pivette sampling method than those obtained using the Bouyoucos hydrometer.
657
surface depression or cavity to the stagnation pressure based on the centre-line v~ocity of the jet in the neighbourhood of the surface. The second, a displaced-liquid analysis, related the weight of the liquid displaced from the cavity to the nomentum of the jet. Numerous experiments were conducted in which the cavity depth, diameter or width, and peripheral lip height were measured. The role of surface tension in affecting the cavity depth was considered and the phenomenon of drop formation was examined. Some attention was given to the case of a plane jet impinging on a moving liquid. It was found that the experimental data fit into the framework of these analyses quite consistently. BARAHONAFERNAD~ J. A., 1962. The use of Raydist in the survey of a bank offshore Lourenco Marques. Int. Hydrogr. Rev., Suppl., 3: 7-13. The example shown is typical of a very accurate offshore hydrographic survey, only possible with modern methods of radio navigation, and represents an interesting contribution to the better knowledge of the Mozambique Channel. Furthermore, the use of Raydist on the hydrographic ship, Almirante Lacerda has provided, as a result of the normal soundings, a large numher of current observations through the comparison of dead reckoning and Raydist positions. They show, at this stage, the very complex structure of the circulation in the Mozambique Channel, near L o u r e n ~ Marqu6s, with a main S.W. current offshore, a nearshore N.E. counter-current and several eddies in betw~n. B~att,rEs H., M. B~N~s and D. M. FnqLAYSOS, 1963. The seasonal changes in body weight, biochemical composition, and oxygen uptake of two common Borco-Arctic cirriped~, Ba/anus balanoides and B. balanus. J. Mar. Biol. Ass., U.K., 43 (1): 185-211. The seasonal changes in the body weight and composition of two common boreo-arctic species of cirripedes, Balanus balanoides and B. balanus have been followed. At a constant size (age under constant growth conditions) the body weight is closely related to the season. Increase in body weight takes place rapidly during the spring as reserves arc laid down. These reserves arc subsequently utilized for gonadal development. The changes in B. balanus are more gradual than in B. balanoides and piobably reflect differences in the habitat conditions. The reserves, although contributing to the gonads, are not themselves adequate for their total tissue. On copulation, body weight is grossly reduced and there is an uptake of water which is replaced when moulting is resumed after the reproductive anecdysis. The total changes in weight during growth are examined. Carbohydrate, fats, and proteins, are stored : the relative changes in these with season are examined. The seasonal changes in oxygen uptake of isolated whole bodies are related to the changes in comvosition and activity of the tissue. BAgN~ H., M. BAgNF.S and D. M. FXNLAYSON,1963. The metabolism during starvation of Balanus balanoides. J. Mar. Biol. Ass., U.K., 43 (1): 213-223. Changes in weight and biochemical composition of Balanus balancides when starved have been determined on summer and autumn animals. When there are considerable carbohydrate reserves these are first utilized, but, after they have fallen to about 10 per cent of the body weight, protein and lipid are used as metabolic substratvs. When carbohydrate reserves are present in quantity the moulting frequency is proportional to the amount present. In animals without carbohydrate reserves, protein and lipid are used immediately food is withheld. The drain ofexoskeleton formation on metabolism is relatively small compared with that in many other crustaceans. Protein and lipid can both provide the glucose necessary for chitin formation in a starved animal. The temperature coefficient of moulting frequency depends upon the substrate used; with the carbohydrate the Q~0 value approximates to 2-0, but when protein and lipid are being used it approaches unity. There is some reduction in oxygen uptake of isolated bodies on starvation when carbohydrate is being utilized. There is a gross discrepancy hetwven the oxygen demand as measured in isolated bodies and the available substrate; respiration is probably reduced during inanition. It is suggested that the moulting cycle is coupled to the metabolic activity in an obligatory fashion rather than being dominated by the kind of hormonal control found in decapods. BASCOMn C. L. and D. T. PglTC,ARV, 1963. A Cartesian hydrometer and its application t o sedimentation analysis. J. Sci. Inst., 40 (1): 30-31. The hydrometer described is particularly suited to sedimentation analysis. It consists of a Perspex framework covered by a thin rubber diaphragm. Manometer readings obtained axe sensitive to 0.00015 specific gravity units and the hydrometer can be adjusted to cover various ranges. Results for particle size analysis of six soils show better agreement with the standard pivette sampling method than those obtained using the Bouyoucos hydrometer.