The phamacological and anthelmintic action of Lysimachia clethroides were examined. Upon examining the action of water, ether, alcohol and acetone extrcts of the root on smooth muscle, it was found that the active principle was weakened by heating. Water and ether extracts inhibited the dehydrogenase of the worm. In 50 percent of 8 areas studied, Taenia were completely eliminated with 2.5-4.0 gm doses of the ether extracts, and no toxic effect was observed by the administration of the above-mentioned doses.
