I90 PRIMULACEAE. 



celled, with a free central placenta rising from the base; fruit a 

 capsule; seeds several or many; endosperm fleshy. 



Stems short; leaves in a basal rosette. 278. Dodecatheon, 190. 



Stems elongated, leaf-bearing. 



Leaves clustered near the summit of the stem. 279. Trientalis, 191. 

 Leaves alternate or opposite, not clustered. 



Flowers in axillary spikes; leaves punctate. 280. Naumburgia, 191. 

 Flowers solitary, axillary; leaves not punc- 

 tate. 

 Flowers sessile, small. 281. Centunculus, 191. 



Flowers pedicelled, large. 282. Steironema, 191. 



278. DODECATHEON. Shooting Star. 



Perennial smooth or viscid-puberulent stemless herbs; leaves 

 all in a basal cluster, oblong or spatulate ; flowers showy, nodding, 

 solitary or in an umbel on a scape, with an involucre; calyx 

 deeply 5-cleft; corolla with a very short tube, 5-parted, purple or 

 white ; filaments distinct and short or united into a tube ; capsule 

 ovoid or oblong, many-seeded. 



Filaments united into a tube half as long as the anthers. 



Plant glabrous. D. vulgare. 



Plant viscid-puberulent. D. puberulum. 

 Filaments free or filament-tube very short. 



Plant glabrous. D. conjugens. 



Plant viscid-puberulent. D. viscidum. 



Dodecatheon vulgare (Hook.) Piper. Glabrous throughout, 15-45 cm. 

 high; leaves spatulate-oblanceolate, obtuse, entire or rarely denticulate, 

 5-10 cm. long, narrowed into a winged petiole as long; umbels 5-20-flowered ; 

 bracts of the involucre triangular-lanceolate, acute, 6-20 mm. long; pedicels 

 1-6 cm. long; calyx-lobes broadly lanceolate, acute or acuminate, not much 

 longer than the tube; petals purple, 1 cm. long; stamineal tube yellow, half as 

 long as the purple anthers; capsules ovoid, 6-9 mm. long, splitting into 5 teeth 

 at the apex when mature. Wet meadows rare. 



Dodecatheon puberulum (Nutt.) Piper. {D. cusickii Greene.) Re- 

 sembling D. vulgare very closely, but viscid-puberulent throughout; leaves 

 usually smaller; scapes 10-30 cm. high. Stony hillsides, common. A white- 

 flowered form is occasionally found. 



Dodecatheon conjugens Greene. Glabrous throughout, 10-30 cm. high; 

 leaves 2 or 3, rarely more, oblanceolate, obtuse, entire, 5-10 cm. long, narrowed 

 at base into a short petiole; flowers usually solitary, less commonly 2, 3 or 

 more; calyx-lobes oblong-lanceolate, acute, twice as long as the tube; petals 

 15-20 mm. long, dark-purple; capsules oblong, 10-12 mm. long, cirumscissile 

 near the top, then deeply splitting into truncate teeth. Low copses, rare. 



Dodecatheon viscidum Piper. Similar to D. conjugens but larger and gland- 

 ular-puberulent throughout; leaves lanceolate to oblong; calyx-lobes four 

 times as long as the tube. In moist meadows near Spangle. 



