There are many kinds of sushi in Japan today. Concerning theorigin of this food, the following hypothesis has been established: theprimitive sushi was Narezushi (a kind of fermented food made with fishor other games, cooked-rice and salt) , which was devised by ricecultivatorsin Southeast Asia to preserve fish, flesh and fowl from decay,and was introduced through China. Some scholars argue thatNarezushi-making was introduced with rice-cultivation to Japan.It is not clear what the sushi in ancient Japan was. Nevertheless,many people, including some scholars, identify the prototypical sushiwith Funazushi, Narezushi of "crucian," which is often served today inOhmi (Shiga prefecture) .One of the reasons for such a view is that Funazushi in Ohmi has alone history. The name of this sushi is noted in En2i-shiki (延喜式),one of the oldest documents in Japan (completed in 927) , so we mightconclude that its birth occured over 1000 years ago.Secondly, today's Funazushi has some primitive characters whichare suggestive of prototypical sushi:1.Funazushi is made of fish (crucian) , cooked-rice and salt only,with neither spices nor starters for fermentation.2.This has a fermentation time of occasionally over a year, which isextremely long compared with other Narezushi in Japan.3.This is usually eaten by eating only soured fish and discarding therice.From these points, Funazushi in Ohmi is sometimes described as"the oldest sushi, or the most primitive sushi, in Japan."However, it is not reasonable to regard Funazushi, as observed today,as a prototypical sushi. This is because its cookery has undergonesome changes since the 10th century.Although there is no data clearly showing the recipe for Funazushiin ancient Japan, we can infer it from the articles on Chimin-yaoshu(斉民要術)published in China in the 6th century. According to thisChinese document, the sushi-cookery in those days has a lot in commonwith today's Funazushi-cookery, but a few differences can be recognized.Noteworthy points are as follows:1.Today's Funazushi-making is practiced in summer, which isnoted as a bad season for sushi-making in Chimin-yaoshu.2.In order to make sushi, Chimin-yaoshu teaches us that the fishmust be cut into some pieces, but Funazushi in Ohmi uses the entirefish without cutting it open.3.The period to salt the fish for preparation of Funazushi-making,about three months, is longer than in Chimin-yaoshu.In addition, even compared with the article in an old Japanesecookery-book published in 1689, today's Funazushi-cookery has thesame differences as the above-stated 1. and 3.In the long run, we can understand that the recipe of Funazushiwhich is practiced as a custom in Ohmi today was completed after 17thcentury. Therefore today's Funazushi should not be regarded as aprimitive preserved food.None of today's sushi, including Funazushi, can be identified withthe prototypical sushi. In the present Japan, we can't find sushi-cookeryjust like the recipe noted in Chimin-yaoshu. On the other hand, somefeatures of the ancient cookery have been inherited separately in someforms of Narezushi. In picturing the prototype of sushi, we need to compoundelements of the primitive characters, which remain only partiallyin some of today's Narezushi.