KEY TO THE SPECIES 53 



1. CHAM^NERION (Willow Hekb) 



Herbs with nearly sessile leaves, purple or white flowers, calyx-tube not pro- 

 longed beyond the ovary, and capsule containing numerous silky-tufted seeds. 

 (See Plant Relations, p. 112, Fig. Ill ; p. 113, Fig. 112 ; p. 128, Fig. 134. Also Plant 

 Structures, p. 212, Fig. 185.) 



Chamsenerion (Epilobium) angustifollum (L.) Scop. (Fire-weed). Stem 

 simple, tall, 7-12 dm. high ; leaves scattered, numerous and large, lanceolate, 

 nearly entire ; flowers large, purple, in a long raceme. In the mountains, in newly 

 cleared or burned ground. 



2. EPILOBIUM (Willow Herb) 



Closely resembling Chamcenerion ; the stigma clavate or more rarely 4-lobed 

 (not cleft) ; calyx-tube prolonged beyond the ovary, the capsule long and slender, 

 4-sided. 



1. Epilobium adenocaulon Haussk. (Northern Willow Herb). Stem 

 moderately branched, 4-8 dm. high, glandular-pubescent in the inflorescence ; 

 leaves narrowly ovate to lanceolate, usually more or less serrate ; buds at first 

 nodding ; the petals notched, purplish or merely tinged with pink ; seeds ellipsoids \ 

 with a short beak and white coma. Frequent ; in wet places, creek banks, spring 

 bogs,^etc. 



2, £pilobiuin paniculatum Nutt. (Panicled Willow Herb). Slender 

 annual, paniculately branched above and glandular-pubescent ; leaves linear or 

 nearly so ; calyx-tube shorter than its lobes ; petals cuneate notched ; capsule 

 fusiform ; the seeds black. Dry banks and open copses. 



3. ONAGRA (Evening Primrose) 



Stoutish erect herbs, nearly simple, with alternate leaves, yellow nocturnal 

 flowers, elongated calyx -tube, 4-celled ovary and 4-angled capsule. 



1. Onagra strigosa Rydb. (Evening Primrose). Grayish, with a short stiff 

 pubescence ; leaves obovate or oblanceolate below, becoming lanceolate -upward ; 

 flowers in a leafy-bracted spike ; calyx-segments with free tips ; capsule 2-3 cm. 

 long. Sandy stream-banks. 



4 GALPINSIA (Primrose) 



Perennial herbs, often with woody base freely branched, elongated slender 

 calyx-tube, broad yellow corolla, elongated capsule narrowed at base and more or 

 less curved. 



1. Galpinsia Hartwegi (Beuth) Britt. (Hartweg's Primrose). Low and 

 branched from the base, with whitish pubescence ; leaves from linear to lanceo- 

 late, nearly entire ; flowers 3-4 cm. broad ; the petals rhombic-obovate ; capsule 

 cylindrical ; the seeds minutely tuberculate. 



5. MERIOLIX (Primrose) 



Perennial from a persistent woody base, moderately branched, the leaves 

 narrow and sharply dentate, the flowers regular and axillary, the disk-like stigma 

 4-toothed and the capsule sessile, 4-angled. 



1. Meriolix seTrulata(Nutt.) Walp. (Toothed-leaved Primrose). Erect, 2-3 

 dm. high, slightly pubescent ; leaves linear-oblong ; profusely yellow-flowered, the 

 petals crenulate. Frequent on sandy and stony ridges. 



