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High-energy sound associated with fright in the dolphin
Oceanographic Abstracts
535
BPaNTON E. 1962. Two new species of Euphausiacea, Euphausia nana and Stylocheiron robustum from the Pacific. Crustaceana, 4(3): 167-179. Zwei neue Arten yon Euphausiiden sind in Planktonproben vom Stillen Ozean gefunden worden. Euphausia nana sp. nov. unterscheidet sich v o n d e r verwandten Art Euphausia pacifica Hanson in Struktureinzelheiten der terminalen und proximalen Forts/itze der Copulations-organe des Mannchens. E. nana ist sehr viol kleiner als E. paeifica. Euphausia nana ist in der Ost-Chinesischen See sowie im Gebiet siJd6stlich von Japan gefunden worden, und lebt m~Sglicherweise geographisch isoliert yon der nOrdlicheren E. pacifica. Die ,,dominierende Stadien" der Larven sind nahezu identisch in beiden Arten. Sic sind abet kleiner bei E. nana als bei E. pacifica. Stylocheiron robustum sp. nov., eine dritte Art der "'Stylocheiron maximum Gruppe", bewohnt die warmen Gew~isser des zentralen und westtropischen Stillen Ozeans, und wurde auch von SiidAfrika gemeldet. BRODSKIY K. 1962. On biogeographical division of pelagical zones of the southern hemisphere according to the distribution of Calanus species (Copepoda). (Abstr. symp. Antart. Biol.) Polar Rec. 11(72): 324. Also: SCAR Bull. p.12. In 1959, at the First International Oceanographical Congress, there was reported the scheme of division of south Pacific Ocean pelagial based on data which were obtained by the third cruise of the Soviet Antarctic expedition on board the research ship Ob. The analysis of plankton samples has been gathered by the first and second cruises of that expedition and critical review of published data confirmed the supposition that zones established for the south Pacific Ocean are the same for all the oceans around the Antarctic. The characteristics of the typical species of biogeographical zones have been studied by means of biometrical treatment of some morphological features. This analysis has shown that the variability of these species has a smaller amplitude as compared with the species of similar northern latitudes. It is connected with the less degree of the underspecific differentiation of the southern species. Nevertheless, biometric analysis has revealed the distinct clinal variability of the body size of adult females of the southern Calanus species. The clinal variability is postulated by the geographical position of the investigated specimens. We stress now that the "real" Antarctic species have the features as from the geographical point of view (the Area) so from the ecological (the character of the variability). Both sides of this aspect are very close together and it is very difficult sometimes to separate the influence of geographical and ecological factors. So the areas of C. propinquus and C. acutus well define the Antarctic zone or biogeographical region. The body length of ripe females of these species decreases regularly from south to north from 5'58 and 5'20 ram, in 1at. 70 to 65°S and from 5"84 to 4"70 m m in lat. 65 to 60°S. The limit of areas of these species and of the Antarctic zone are the same: the coast of Antarctica and Antarctic convergence. The area of C. simillimus defines "interzonal region" of the Antarctic divergence up to lats. 45 to 50°S and sometimes to lat. 40°S to the so-called sub-Antarctic divergence. Variation in body length of females of this species is quite different from the two preceding species. In the central part of the area (Antarctic convergence) females of C. simillimus are smaller. Notal or Austral zone Oats. 50 to 55°S and 35 to 40°S) is well defined by the areas of C. tonsus and C. australis. CALDWELL M. C., R. M. HAUGEN and D. K. CALDWELL 1962. High-energy sound associated with fright in the dolphin. Science, 138(3543): 907-908. A sound produced by the Atlantic bottlenose dolphin (Tursiops truncatus) under conditions of fright is described and iUustrated. It is suggested that a similar sound may be the basis of the long-distance alarm signal reported in other cetaceans. CECCALDI H. J. 1962. Sur une methode de recolte du macroplancton. Rec. Tray. Sta. Mar. Endoume, Bull. 26, (41): 3-6. The method for catching macroplankton by experienced divers, increases the number of animals caught. A large underwater area can easily be explored and desired specimens selected at will. The advantages of this method are doubled by the fact that the animals can be caught and taken to the laboratory without damage. CHAPPELEAR J. E. 1962. Shallow-water waves. J. Geophys. Res., 67(12): 4693-4704. The physical problem is to calculate the profile and velocity components of a wave, subject to the conditions that the effects of viscosity and surface tension can be neglected. The flow is required to be steady, irrotational, and two dimensional, and the depth of the water is assumed to be small and constant. The shallow-water approximation, first proposed by Friedrichs, is employed, and two additional orders of approximation, beyond the three calculated by Keller, are obtained. The formulas describing the solitary wave are obtained as a special case, and the velocity of the solitary wave so obtained is found to agree almost exactly with the 13oussinesq-Rayleigh formula c=a/g--~ + H/d), where c is the wave velocity, d is the depth, a n d / 4 is the wave height. This velocity ditf¢rs by no moro than 2 per cent from the experimental values of STEPHAN and DAILEY.
535
BPaNTON E. 1962. Two new species of Euphausiacea, Euphausia nana and Stylocheiron robustum from the Pacific. Crustaceana, 4(3): 167-179. Zwei neue Arten yon Euphausiiden sind in Planktonproben vom Stillen Ozean gefunden worden. Euphausia nana sp. nov. unterscheidet sich v o n d e r verwandten Art Euphausia pacifica Hanson in Struktureinzelheiten der terminalen und proximalen Forts/itze der Copulations-organe des Mannchens. E. nana ist sehr viol kleiner als E. paeifica. Euphausia nana ist in der Ost-Chinesischen See sowie im Gebiet siJd6stlich von Japan gefunden worden, und lebt m~Sglicherweise geographisch isoliert yon der nOrdlicheren E. pacifica. Die ,,dominierende Stadien" der Larven sind nahezu identisch in beiden Arten. Sic sind abet kleiner bei E. nana als bei E. pacifica. Stylocheiron robustum sp. nov., eine dritte Art der "'Stylocheiron maximum Gruppe", bewohnt die warmen Gew~isser des zentralen und westtropischen Stillen Ozeans, und wurde auch von SiidAfrika gemeldet. BRODSKIY K. 1962. On biogeographical division of pelagical zones of the southern hemisphere according to the distribution of Calanus species (Copepoda). (Abstr. symp. Antart. Biol.) Polar Rec. 11(72): 324. Also: SCAR Bull. p.12. In 1959, at the First International Oceanographical Congress, there was reported the scheme of division of south Pacific Ocean pelagial based on data which were obtained by the third cruise of the Soviet Antarctic expedition on board the research ship Ob. The analysis of plankton samples has been gathered by the first and second cruises of that expedition and critical review of published data confirmed the supposition that zones established for the south Pacific Ocean are the same for all the oceans around the Antarctic. The characteristics of the typical species of biogeographical zones have been studied by means of biometrical treatment of some morphological features. This analysis has shown that the variability of these species has a smaller amplitude as compared with the species of similar northern latitudes. It is connected with the less degree of the underspecific differentiation of the southern species. Nevertheless, biometric analysis has revealed the distinct clinal variability of the body size of adult females of the southern Calanus species. The clinal variability is postulated by the geographical position of the investigated specimens. We stress now that the "real" Antarctic species have the features as from the geographical point of view (the Area) so from the ecological (the character of the variability). Both sides of this aspect are very close together and it is very difficult sometimes to separate the influence of geographical and ecological factors. So the areas of C. propinquus and C. acutus well define the Antarctic zone or biogeographical region. The body length of ripe females of these species decreases regularly from south to north from 5'58 and 5'20 ram, in 1at. 70 to 65°S and from 5"84 to 4"70 m m in lat. 65 to 60°S. The limit of areas of these species and of the Antarctic zone are the same: the coast of Antarctica and Antarctic convergence. The area of C. simillimus defines "interzonal region" of the Antarctic divergence up to lats. 45 to 50°S and sometimes to lat. 40°S to the so-called sub-Antarctic divergence. Variation in body length of females of this species is quite different from the two preceding species. In the central part of the area (Antarctic convergence) females of C. simillimus are smaller. Notal or Austral zone Oats. 50 to 55°S and 35 to 40°S) is well defined by the areas of C. tonsus and C. australis. CALDWELL M. C., R. M. HAUGEN and D. K. CALDWELL 1962. High-energy sound associated with fright in the dolphin. Science, 138(3543): 907-908. A sound produced by the Atlantic bottlenose dolphin (Tursiops truncatus) under conditions of fright is described and iUustrated. It is suggested that a similar sound may be the basis of the long-distance alarm signal reported in other cetaceans. CECCALDI H. J. 1962. Sur une methode de recolte du macroplancton. Rec. Tray. Sta. Mar. Endoume, Bull. 26, (41): 3-6. The method for catching macroplankton by experienced divers, increases the number of animals caught. A large underwater area can easily be explored and desired specimens selected at will. The advantages of this method are doubled by the fact that the animals can be caught and taken to the laboratory without damage. CHAPPELEAR J. E. 1962. Shallow-water waves. J. Geophys. Res., 67(12): 4693-4704. The physical problem is to calculate the profile and velocity components of a wave, subject to the conditions that the effects of viscosity and surface tension can be neglected. The flow is required to be steady, irrotational, and two dimensional, and the depth of the water is assumed to be small and constant. The shallow-water approximation, first proposed by Friedrichs, is employed, and two additional orders of approximation, beyond the three calculated by Keller, are obtained. The formulas describing the solitary wave are obtained as a special case, and the velocity of the solitary wave so obtained is found to agree almost exactly with the 13oussinesq-Rayleigh formula c=a/g--~ + H/d), where c is the wave velocity, d is the depth, a n d / 4 is the wave height. This velocity ditf¢rs by no moro than 2 per cent from the experimental values of STEPHAN and DAILEY.