Silphium (also known as silphion or laser) was a plant of the genus Ferula. Generally consiered to be an extinct "giant fennel" (although some claim that the plant is really Ferula tingitana), it once formed the crux of trade from the ancient city of Cyrene for its use as a rich seasoning and as a medicine. It was so critical to the Cyrenian economy that most of their coins bore a picture of the plant (illustration, right).