PAPAVERACEAE 461 



ous. Stamens numerous : filaments slender. Ovary with 3-4 nerviform placentae : style 

 manifest, the dilated tip 2-4-lobed : stigmas black : ovules numerous. Capsule elon- 

 gated, often stalked, bristly. Seeds numerous, crested : scrobiculate-reticulated. Endo- 

 sperm oily. Embryo minute, basal. CELANDINE POPPY. YELLOW POPPY. 



1. Stylophorum diphyllum (Michx. ) Nutt. Foliage glaucous, sparingly pubescent. 

 Stem 2-5 dm. tall, often simple: leaves basal and cauline, 1-2.5 dm. long; blades 

 petioled, 2-pinnatifid, the segments broadened upward, lobed or crenate-undulate : flowers 

 2-4 at the top of the stem : sepals 2, hirsute : corolla deep yellow, 2-3 cm. broad : petals 

 obovate, rounded at the apex : capsule ovoid or oval, about 2-5 cm. long, hirsute, acute at 

 each end. 



In low woods, Pennsylvania to Wisconsin, Tennessee and Missouri. Spring. 



4. CHELIDONIUM L. 



Biennial or perennial caulescent herbs, with a yellow sap, and erect branching stems. 

 Leaves alternate : blades pinnately dissected, pubescent. Flowers perfect, yellow, numer- 

 ous. Sepals 2. Petals 4, relatively small, very deciduous. Stamens numerous : filaments 

 slender. Ovary 1 -celled with 2 placentae : styles 2, distinct : stigmas barely dilated, 

 2-lobed. Ovules numerous, inserted on the 2 nerviform placentae. Capsule narrow, 

 2-valved, the valves separating to the base. Seeds numerous, crested, the testa shining. 

 Endosperm oily. Embryo minute. 



1. Chelidonium ma jus L. Foliage bright green, sparingly pubescent below. Stem 

 erect, 2-7 dm. tall, branching, succulent : leaf-blades pinnatifid or bipinnatifid, 1-3 dm. 

 long, the segments with rounded lobes or teeth, the lower petioles elongated, the upper 

 ones very short : cymes peduncled : pedicels 1-5 cm. long : sepals 2, boat -shaped, about 7 

 mm. long, villous below the apex : petals 4, yellow, suborbicular, rounded or emarginate 

 at the apex : filaments clavate, a little more than \ as long as the petals : capsules slender, 

 3-5 cm. long, constricted between the seeds. 



In waste places, common in eastern North America. Naturalized from Europe. Spring to fall. 

 ROCK POPPY. CELANDINE. 



5. PAP AVER L. 



Annual or perennial glaucous or pubescent herbs, with milky sap, and erect, usually 

 branched stems. Leaves alternate, sometimes mainly basal : blades usually lobed or dis- 

 sected. Buds drooping. Flowers perfect, showy, variously colored, on elongated pedun- 

 cles. Sepals 2 or rarely 3. Petals 4 or rarely 6, broadened upward. Stamens numerous : 

 filaments slender. Ovary with 4-20 septiform placentae : stigmas united into a disk-like 

 or variously shaped crown-like body. Ovules numerous. Capsule subglobose to oblong, 

 opening by 4-20 pores or cracks under the stigma. Seeds naked, crestless. POPPY. 



Plants hirsute : leaf-blades pinnately divided : capsule oblong-obovoid. 1. P. dubium. 



Plants glaucous : leaf-blades lobed : capsule subglobose. 2. P. somntferum. 



1. Papaver dubium L. Annual, slender, hirsute. Stem erect, often branched at 

 the base and above, 2-7 dm. tall : leaf-blades pinnately divided, the divisions entire, 

 toothed, or pinnatifid, the ultimate segments acute : flowers scarlet, 5-7 cm. broad, on 

 long slender stalks : sepals oblong or oval, about 1.5 cm. long : petals undulate or crisped : 

 filaments filiform : capsule oblong-obovoid, 1.5-2 cm. long, glabrous. 



In fields and waste places, Pennsylvania to North Carolina and Tennessee. Summer. Naturalized 

 from Europe. 



2. Papaver somniferum L. Annual, stoutish, glabrous, glaucous. Stem erect, 3-10 

 dm. tall, simple or sparingly branched : leaf -blades oblong to ovate, 6-20 cm. long, in- 

 curved, lobed and toothed, the lobes toothed, sessile, the cordate base clasping : flowers 

 long-stalked, white to purple, often variegated, 4-10 cm. broad : petals about as broad as 

 long, undulate : filaments somewhat club-shaped : capsule subglobose or slightly narrower 

 above the middle, 2-3 cm. long, glabrous. 



In waste places, naturalized or adventive in the eastern United States. Native of the Mediterra- 

 nean region. OPIUM POPPY. GARDEN POPPY. 



6. ARGEMONE L. 



Annual or biennial herbs, with glaucous foliage and a yellow sap. Stems erect, branch- 

 ing. Leaves alternate : blades sessile or clasping, incised, pinnatfid, the segments tipped 

 with bristle-like spines. Buds erect. Flowers perfect, showy, white or yellow. Sepals 

 2-3, hooded or horned. Petals 4-6, broadened upward. Stamens numerous : filaments 



