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ceed equallywell iti both sections ; but the best named varieties 

 are mostly found in the south parts of Omote-Nippon. They 

 grow and fruit freely in a variety of soils. The colour and 

 quality of the fruits as well as their yield seem to be promoted 

 by planting them on heavy, but well-drained loams. They' 

 are very water-loving in habit and require a constant and 

 sufficient supply of soil water. Soil variable in their water 

 contents are unfit for their cultivation, causing the premature 

 dropping of the fruit, especially in and after the rainy season 

 (" Tsuyu "). 



CITROUS FRUITS. 



Citrous plants can grow from about 37 degrees N. L. 

 southwards. Their growing centers, however, are located 

 from 35 degrees N. L.. southwards, but owing to the influence 

 of the warm current (Kuroshiwo in the Pacific Ocean and 

 Tsushima Current in the Sea of Japan) their north limit extends 

 up to the 37 degrees N. L. on the sea coast. Inland valleys 

 of central Japan are not favourable for the growth of citrous 

 fruits because of the effects of high altitude. Only in a 

 smail part of Shinano and Kai some of the hardiest kinds are 

 grown but not on a commercial scale. 



Near the north limit or frontier of the citrous area are 

 trifoliate orange (Aegle Sepiaria), " Yuzu " and often " Daidai" 

 (Bitter orange, Citfous Bigaradia). Next follow the mandarin 

 (C. Nobilis), Kinkans (C. N. Var. Microcarpa) and " Natsu- 

 riiikan " (C. Bigaradia Var. Sinense). Then come the region 

 of sweet oranges (C. Aiirantium) whose north limit extends to 

 about 35.5° N. L. on the sea coast. South of the oranges 

 come the pomelos and grape fruits (C. Decumana), followed 

 by Fingered Citrons (C. Medica Var. Chirocarpus), lemons 

 and citrons. Their north limits are likely to coincide with 

 those of the Myrica and the olives. The limes are not yet 

 cultwated in our country. - The flavour of the dessert kind of 

 citrous fruits, such as oranges, pomelos and mandarins become 



