Kiyoshi AWAZU

Underground Turtle
The character Urashima Taro appears in the book Tango Fudoki from the fourth or fifth century. After that, he appears again in Nihon Ryoiki and Otogizoshi from the Meiji Era. In the Showa Era, Osamu Dasai wrote abouthim.
I am also interested in other sources about sea turtles.
A pictorial book of the reptiles describes the historical assumption is that, at the end of the Paleozoid era, turtles were differenciated from the ancestors of cotylosaurus.
The other assumption is that their skin and flesh were combined together to form the upper section of the shell, the carapace, and the lower section, the plastron. Turtles thus have alligator terrapins as their relatives.
Turtles were pilots of foresight and fortune tellers in ancient China and were geometrically similar to the Chinese octagon direction board.
This similarity in form lead to a similarity in function - the board was used for reading faces and for the auspicious location of houses and the turtle was taken as the mysterious pilot and guardian deity of the people.
There are some shrines of this sort in kyushu. The turtles that appear here used to live around Okinawa. The older ones have been swimming on the ocean bottom for two hundred years. The cast impressions of the 18 turtles of Okinawa have now punched through the underground walls of Yokohama to make their appearance.

I hear that there is an American composer who wrote a musical piece in which the theme is sea turtles.
I understand this piece is four hours long. The violin piece is played by the composer while he sits in a gigantic dome. I imagine that he dreams about the time when he himself became a turtle.
I am probably getting into the legend of the turtle that explains how Urashima Taro came to live eight hundred years out of his one thousand years.