1) This experiment is aimed to provide information of heading characteristics and to explore the possibility of hastening the generation of Ceylon varieties using the short daylength treatment, so as to shorten the breeding period. This experiment was conducted at the Central Rice Breeding Station, Batalagoda, Ceylon during Maha 1964/65 and Maha 1965/66.
2) 18 Ceylon main varieties differing in ages were tested with 2 Taiwan varieties. Sprouted seed of each variety was seeded in cement pots in rows and thinned out to 5 plants per variety. Short daylength of 10 hours was made by moving the pot from the dark room into the open and reverted again to the dark room.
3) Result of short daylength treatment from different stages of growth till heading showed the varietal difference of seeding-to-heading interval in wide range. Varieties used in this experiment was grouped into 6 on their photoperiod sensitivity and basic vegetative growth. Group V of Taiwan varieties were photoperiod insensitive and others sensitive more or less. Short daylength treatment is most effective in long age photoperiod sensitive varieties.
4) Any variety tested in this experiment will be able to complete 3 generations in a year under suitable daylength conditions. Short daylength treatment is enough to commence 10 or 15 days after seeding.
5) Effect of short daylength appeared 10 to 15 days after commencement of the treatment in photoperiod sensitive varieties and increased till 25 to 30 days in sensitive varieties and upto 40 days in low sensitive varieties.

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This experiment was conducted at the Department of Agriculture, Ceylon in 1962 to 1963 during the author's stay there, to investgate the growth and yield of indica rice. The results obtained are summarized as follows:
1. Application of urea as compared with ammonium sulphate in acid lateritic paddy field significantry out yielded.
2. In general effect of nitrogen application to the acid lateritic soil in low cation exchange capacity on the yield of rice have a little response, particularly acid nitrogenous fertilizers have a very little response due to the root rot by the presence of sulfides in the soil. While the acid lateritic soil in high cation exchange capacity have a good response.
3. By application of ammonium sulphate in strong acid lateritic soil and ground water podzolic rice soil, physiological activity of roots considerably decreased in the presence of sulfides. Moreover, absorption of nitrogen was retarded and metabolism of carbohydrate became abnormal.

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The author attempted to compare cultivated formosan species in Japan with that in TAIWAN. in the results of the comparison with respect to characteristics of leaves no difference was observed and distinct difference in number of veins and that of serrations was not observed between cultivated species in Japan and that in TAIWAN.
But the cultivated species in Japan has considerable smaller size both in length and width of the leaf. This is considered to show a tendency of reduction in the size of leaf with shifting of tea plant northward.

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