Abstract
This paper examines the form of Tsune-goshos in Seiryo-den of three palaces, Nijo-Tomikoji (1317〜1336), Oeido (1402〜1443), Kosho-do (1456〜1590). As the result, the following facts have been clarfied. 1. The Tsune-gosho of Kosho-do Palace consists of three rooms called Tsune-gosho, Rentai, and Hisashi which are respectively in Moya, Hisashi, and Mago-bisashi. 2. The characteristic fittings such as Chodai-gamae, Naka-bashira, different level floors, Shitomi lattice, etc. appeared with the expansion and the progress of the Tsune-gosho. 3. The form of Tsune-gosho of Kosho-do Palace is inherited in the form of three rooms used for official affairs in Tsune-gotens built in Edo period. 4. The room in South row (Edo preiod) which corresponds with the Hisashi (Kosho-do) becomes similar to the form of ordinary Gedan, by losing the factors which image "Hisashi". 5. The Gedan of the three rooms of south row is the transitional form of Hisashi to Gedan, and this is one of the steps in the forming process of Jodan.