On the Relation between the Appearance of Spores of the Laver (Porphyra tenera) and the Environmental Conditions-II

For the purpose of finding out the best condition to set the collector for laver in the sea to get a best crop, a study was made through the following methods from late September to the early November. 1. Daily observation on the vertical change in temperature and chlorinity of sea water in about one meter intervals from the surface to the bottom. In the meantime, air temperature and wind were also recorded. 2. Counting the laver-germlings appeared on the collector which have been set every day in the sea. 3. Calculation of the laver-spores liberated from the Conchocelis which have been set in the sea after over-summering in the laboratory. The results may be summerized as follows: 1. The laver-spores are apt to appear in large quantities within a few days after the occur-rence of vertical turbulance of sea water. 2. Hydrographic and atmospheric conditions havc some influence on the liberation of spores from the Conchocelis. 3. There seems to be a closer correlation between the appearance of laver-spores in nature and the liberation of spores from the Conchocelis set in the sea.