The Seed of Life is the companion symbol to the larger flower of life, and consists of its central circles. It is also very potent, although it might have slightly different effects on the human psyche than the Flower of Life.
I vectorized this with Inkscape from a public domain line drawing I found on Wikipedia by a user named "Rama". I also have posted this SVG file to the Wikimedia Commons:
http://commons.wikimedia.org/wiki/Image:Caduceus.svg
Original drawing:
http://commons.wikimedia.org/wiki/Image:Caduceus_large.jpg
