Thirty different genera of household ornamental plants have been investigated to determine the loci and natures of potential toxins and any injurious effects produced in experimental animals. Different plant parts were tested for alkaloids, glycosides, steroids, saponins, and cyanogenic glycosides. At least seven genera showed detectable concentrations of alkaloids. Glycoside tests were variable, and there was an indication that several species may contain steroid components. Sixteen genera showed positive saponin foam tests. None of the species were clearly cyanogenic. Preliminary biologic screening on rats and mice is given.