This paper deals with the latitudinal mean value of the distribution of 190 spec es of marine mollusca from Hokkaido. Results (Table 1) show that Hakodate, Otaru and Yagishiri Island are most strongly affected by the Warm Tsushima Current among the localities. On the other hand, such localities as Monbetsu, Utoro and Akkeshi are more influenced by the Cold Oyashio Current compared with the other places in this study.

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Krijgsman (1928) has pointed out that phosphate contained in the globules in the calcareous cell of the midgut-gland of Helix has a buffer action in the digestive process. When the animals (Bradybaena similaris (Ferussac)) were laid in the container without food for about a month, some globules stained dark with hematoxylin are often observed in the calcareous cell of the midgutgland. These globules dark stained by hematoxylin are absent in the animals under the natural condition or fed with artificial food. Calcium salt in solution is assumed to be present in the inner part of these globules. Sometimes, calcium deposition is proved to be in these globules of the calcareous cell in the starved animals. The presence of calcium salt in solution or in deposit in these globules of the calcareous cell is considered to be related to the absence of the buffer action for digestive process in the starved animals. This consideration agrees with the Krijgsman's note described above. Moreover, the results of the present experiment coincides with that of Hirsch (1917), who reported that more calcium globules were found in the calcareous cell of the midgut-gland of starved specimens of Murex than fed animals. The auther will make more precise studies in the future on the function of the calcareous cell in the digestive process.

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