This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Glaucous herbs, with yellow sap, spiny-toothed leaves and large showy flowers. Sepals 2 or 3. Petals 4-6. Stamens ∞. Placentae 4-6, many-ovuled. Style very short or none. Stigma dilated, 3-6-radiate. Capsule prickly, oblong, dehiscent at the apex by valves. Seeds numerous, cancellate. [Greek, an eye disease, supposed to be relieved by the plant so called.]
A genus of about 10 species, natives of America. Type species: Argemone mexicana L.
Petals yellow, or rarely cream-colored; flowers nearly or quite sessile.
Petals white, or pinkish.
Flowers distinctly peduncled; spines of the sepal-tips nearly erect.
Flowers sessile or nearly so; spines of the sepal-tips spreading.
Argemone mexicana L. Sp. Pl. 508. 1753.
Stem stout, 1°-2° high, simple or sparingly branched, spiny or sometimes nearly unarmed. Leaves sessile, clasping by a narrowed base, 4'-10' long, 2'-4' wide, glaucous, white-spotted, runcinate-pinnatifid, spiny-toothed and more or less spiny on the veins; flowers yellow or cream-colored, sessile or subsessile, 1'-2' broad; sepals acuminate, bristly-pointed; stamens 4"-5" long; filaments slender, much longer than their anthers; stigma sessile or nearly so; capsule I' long or more.
In waste places, Massachusetts to New Jersey, Pennsylvania, Florida and Texas. Also in ballast about the northern seaports. Adventive from tropical America. A common weed in the American tropics, and introduced into the Old World. The seed yields a valuable painter's oil. June-Sept. Bird-in-the-bush. Devil's-fig. Yellow, Flowering or Jamaica thistle.
A. albiflora Hornem. Hort. Havn. 469. 1815.
Commonly stouter and taller than the preceding species. Leaves pinnatifid or pinnately lobed, glaucous or green, not blotched, but sometimes whitish along the veins; flowers white, usually much larger, 3'-4' broad, distinctly peduncled; petals rounded; spines of the sepal-tips stouter; capsules i'-1 1/2' long.
Argemone intermedia Sweet, Hort. Brit. Ed. 2, 585. 1830. Stem stout, prickly, glabrous and glaucous, often 2o high or more. Leaves lobed or pinnatifid, very prickly, usually whitish-blotched; flowers large, white, sessile or nearly so, 3'-4' wide; petals rounded; spines of the sepal-tips spreading; capsule oblong, prickly, about 1' long.
Prairies and plains, Illinois to South Dakota, Wyoming, Nebraska, Texas and Mexico. Has been confused with the preceding species, and with A. platyceras Link & Otto. May-Aug.