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.
The habitat of this plant is the sides of fields, chiefly on calcareous soil. The habit is erect. The plant differs from the smooth-headed Poppy in having the sap dark-yellow on exposure, the leaf lobes larger, the capsule club-shaped, oblong, broadest one-third below stigma, and the lobes of the stigmatic disk bent down. The flowers are large, the petals red, distinct, inversely egg-shaped, or wedge-shaped. Otherwise the plant resembles Papaver dubium (q.v.). The plant is 1-2 ft. in height, and flowers in June and July, being an annual.
The habitat of this plant is chalky cornfields, on dry soil. The habit is erect. The stem is slightly hairy or hairless, with yellow juice. The leaves are divided to the base, once or twice, with lobes with a terminal bristle, rough, linear, nearly smooth. The flowers are violet-blue, with a black disk. The petals fall before midday. The sepals are hairy. The pod is cylindrical, rigid, sparingly hairy above, 3-valved, erect. The seeds are numerous, rough, deeply pitted. The plant is 1 ft. to 18 in. high, flowering in May and June, and is a herbaceous annual.