This section is from the book "British Wild Flowers - In Their Natural Haunts Vol5-6", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
This species is found on heaths. The habit is erect. The plant is down)*. The stem is slender, leafy, angular, rough. The radical leaves are inversely ovate or oblong, spoon-shaped, blunt, with a few wavy teeth, the upper leaves are stalkiess, lance-shaped to linear, running down the stem. The flowers are blue or purple, erect or spreading, in terminal, loose, simple racemes. The lobes of the calyx are nearly equal, awl-like, not so long as the tube. The corolla-lobes are also nearly equal, lance-shaped, acute. The fruit is a 2-3-valved capsule. The plant is 9-24 in. in height, and flowers in August and September. It is a herbaceous perennial.