Biologic evolution

Photograph mussel inside.
It took a picture mainly of Tait and the stalk.

Tait is pulled out.
Tait confirms there is one string in the center.
I see ..bunching... the fine thread from a center string



How of the string for the start was not able to be judged in an internal
photograph.
Tait was pulled from the stalk, and there were no signs that had been put
on the Tait center of the shell.
I think that the possibility of the expansion of the string from the center
and putting the string besides the shell is higher.