RHINANTHACEAE 



1059 



obtuse : corolla white or cream-colored, 2.5-3 cm. long, the lower lip copiously bearded 

 within : capsules ovoid, 10-12 mm long. 



In low thickets and swamps, Newfoundland to Manitoba, Florida and Kansas. 



3. Chelone obliqua L. Similar in habit to C. glabm, but seldom as tall. Leaf- 

 blades often more sharply serrate or incised : bracts and calyx-lobes puberulent and mani- 

 festly ciliolate : corolla pink, fully 2 cm. long, the lower lip rather sparingly bearded. 



In damp thickets and along streams, Virginia to Illinois, south to Florida. 



4. Chelone Lyonii Pursh. Stems 3-8 dm. tall, usually simple : leaf-blades ovate to 

 elliptic, 5-15 cm. long, acuminate, sharply serrate, cuneate, rounded or truncate at the 

 base : racemes 2-5 cm. long : calyx-lobes oval to suborbicular, 6-8 mm. long, like the 

 bracts ciliolate at least at the tip : corolla deep rose-purple, about 2.5 cm. long : capsules 

 ovoid, 11-14 mm. long. 



On damp mountain slopes and summits, Virginia to North Carolina, Tennessee and Georgia. 



10. PENTSTEMON Soland. 



Perennial caulescent herbs, with glabrous glaucous or pubescent foliage. Leaves oppo- 

 site : blades entire, toothed or dissected, sometimes clasping at the base. Flowers in terminal 

 racemes or panicles. Calyx-lobes 5, entire or toothed. Corolla usually showy, rather 

 elongated, 2-lipped. Stamens 4 : filaments about equal in length : staminodium slender, 

 bearded. Styles united : stigma capitate. Ovules numerous. Capsule often ovoid. 

 Seeds wingless, angled or rounded. BEARD-TONGUE. 



Leaf-blades pinnately dissected or pinnately parted. 1. P. dissectm. 



Leaf-blades entire or merely toothed. 



Foliage more or less pubescent or puberulent, sometimes only in the inflores- 

 cence. 

 Stems glabrous below the inflorescence, or rarely puberulent in lines. 



Corolla-tube gradually dilated. 2. P. tubiflorus. 



Corolla-tube abruptly dilated about the middle. 



Calyx-lobes lanceolate to ovate, much less than 1 cm. long. 



Corolla purplish ; tube not gibbous above the point of enlargement. 3. P. Pentstemon. 

 Corolla white or pinkish ; tube gibbous above the point of enlarge- 

 ment. 4. P. Digitalis. 

 Calyx-lobes linear-subulate from a narrowly lanceolate base, becom- 

 ing fully 1 cm. long. 5. P. calycosm. 

 Stems pubescent or puberulent. 



Throat of the corolla less than 1 cm. in diameter. 



Primary branches of the inflorescence elongated or manifest. 

 Stems hirsute or canescent, often glandular. 



Corolla densely bearded in the throat : upper leaves with nar- 

 rowly lanceolate blades. 6. P. hirsutus. 

 Corolla scarcely bearded in the throat : upper leaves with ovate 



or broadly lanceolate blades. 7. P. canctcens. 



Stems puberulent. 



Upper leaves or lower bracts not dilated at the base. 

 Leaf-bases not decurrent on the stem. 



Calyx-lobes lanceolate, at least during anthesis : capsules 



8-10 mm. long. 8. P. australis. 



Calyx-lobes ovate to triangular : capsules 5-6 mm. long. 9. P. pallidua. 

 Leaf- bases manifestly decurrent on the stem. 10. P. multiflorus. 



Upper leaves and lower bracts with dilated and rounded bases. 

 Calyx-lobes acute or short-acuminate : corollas 2 cm. long or 



longer : capsules longer than the calyx. 

 Corolla-tube gradually dilated, the lower lip sparingly 



bearded. 11. P. Mackayanus. 



Corolla-tube abruptly gibbous, the lower lip copiously 



bearded. 12. P. Smallii. 



Calyx-lobes with long slender tips : corollas 1.5 cm. long or 



shorter : capsules shorter than the calyx. 13. P. tennis. 



Primary branches of the inflorescence suppressed or very short. 



Mature calyx-lobes lanceolate : capsules not veined. 14. P. albidus. 



Mature calyx-lobes ovate or ovate-lanceolate : capsules promi- 

 nently veined. 15. P. Guadalupensis. 

 Throat of the corolla over 1 cm. in diameter. 



Staminodium glabrous. 16. P. triflorus. 



Staminodium bearded. 



Corolla less than 3 cm. long: capsules smooth, much longer than 



the calyx-lobes. 17. P. Helleri. 



Corolla over 3 cm. long: capsules prominently veined, about as 



long as the calyx-lobes. 18. P. Cobaea. 



Foliage perfectly glabrous, manifestly glaucous. 



Leaf-blades distinct at the base : corolla lilac or lavender-blue : stamino- 

 dium bearded. 

 Leaf-blades connate-perfoliate : corolladeep scarlet : staminodium glabrous. 



19. P. 



20. P. 



randiflorus. 

 furrayanus. 



1. Pentstemon dissectus Ell. Puberulent. Stems about 6 dm. tall : leaves opposite ; 

 blades pinnately dissected or pinnatifid above, the segments 7-11, linear, 1-2 mm. wide, 





