Horizontal diffusion from an instantaneous source in a nonuniform flow is studied theoretically by use of a transport equation. The treatment is limited to a field of mean velocity having components that are linear functions of the coordinates relative to the center of mass of the patch. Thus, this model may represent the turbulent diffusion from an instantaneous source in a turbulent field in which the characteristic length of large-scale eddies is much larger than the size of diffusing patch. The total dispersion of the patch is determined by the combined effect of diffusion due to the small eddies and of convection due to the larger eddies. The model may interpret partially the observed elongation of diffusing patches in the sea and the orientation of the elongated patches with respect to the mean flow, i. e. the flow in the large-scale eddies.

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Two new species of the Gen. Pseudomma have been found from macroplankton collections made at 1000 m depth in Sagami Bay during the cruise of RV Tansei-maru. A species, P. matsuei can be easily recognized from the other species by the combination of two characters, eyeplate and telson. Another one, P. izuensis allied to P. sarsi and P. truncatum, but can be distinguished by the shape of eyeplate and scale, and also by the armature of telson. Key for the identification of the species belonging to the genus is given.

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For sea water samples collected during the Umitanka-Maru cruise, December 1962-January 1963, of the International Indian Ocean Expedition Program, the content of dissolved carbohydrate was measured by using the phenol sulfuric acid method on which the author intends to report in a succeeding issue of this Journal.
It was shown that low values 0.21-0.39 mg/l were observed at upper levels, while higher values were obtained at levels below 100m.
The values are compared with those hitherto obtained in the Pacific Ocean.
Some discussions are made regarding the possible cause of these low and high values and the unequal vertical distribution of the content of dissolved carbohydrate as observed in the Indian Ocean.

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The content of copper and zinc in sea waters collected on the route from Japan to Antarctica during the fourth and the sixth cruises of the Japanese Antarctic Research Expedition (1959-1960, 1961-1962) on board M. S. SOYA was determined. Copper and zinc were analyzed by the colorimetric method using sodium diethyldithiocarbamate and dithizone respectively. The analytical results showed that the average contents of reactive copper and zinc in the waters of the Southern Ocean was 1.6 μg/l and 7.5 μg/l respectively. As to the Indian Ocean waters, the average values of 1.4 μg/l for copper and 5.5 μg/l for zinc were obtained.

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