BTW Nice picture
Wasson might say, "Soma of it".
According to Wasson, the plant is generally dried. It is also filtered through the kidneys of elk and cattle in some cultures (yes, that means just what it sounds like).
Wasson's theory was that soma in the Hindu pantheon was actually this mushroom; cattle being sacred follows along. Hence the name of his book (as Antonello astutely noted).
[Incidentally, I have a copy of the original numbered edition of 680. They are getting pretty hard to find nowadays.]