A perennial evergreen dogbane plant with herbaceous stem; growing to about 2 meters in height; covered with downy hairs; and with delicate; sky-blue; star-shaped flowers.This highly ornamental plant was discovered by Mr. Tweedie at Tucuman in South America. It is not improbable that indigo might be procured from this Tweedia. Seeds were sent by Mr. Tweedie in 1835 to Mr. Niven of the Glasnevin Garden; Dublin; to whom we are indebted for the opportunity of publishing this desirable novelty.Illustration by Miss Sara Maund; with a coloured engraving depicting the shrub whole; and a coloured engraving of the seed vessel (at right); opened to show the seeds.