RHINANTHACEAE. 259 



5. CHELONE [Tourn.] L. Perennial herbs. Leaf -blades toothed. Flow- 

 ers in congested racemes. Calyx-lobes 5, broad. Corolla 2-lipped, slightly 

 open at the mouth: lower lip with 3 relatively small lobes. Stamens 4: fila- 

 ments pubescent, nearly equally adnate to the corolla: anthers villous. Stami- 

 nodium elongate. Capsules surpassing the calyx. — Turtle-head. 



1. C. glabra L. Stems 3-18 dm. tall, mostly branched: leaf -blades broadly 

 linear to oblong, elliptic, or lanceolate, 6-17 cm. long, rather coarsely toothed, 

 narrowed at the base: calyx 8-10 mm. long: corolla 25-30 mm. long: stami- 

 nodium pubescent at the base : capsules 10-12 mm. long. — Common, in swamps 

 and low grounds. — Fall. — Balmony. Snakehead. 



6. PENTSTEMON [Mitchell] Soland. Perennial herbs. Leaf-blades 

 entire, toothed, or rarely dissected. Flowers borne in racemose or paniculate 

 cymes. Calyx-lobes 5, longer than the tube, sometimes toothed. Corolla 2- 

 lipped, the lips more or less spreading. Stamens 4 : filaments unequally adnate 

 to the corolla. Staminodium elongate. Capsule surpassing the calyx. — Beard- 

 tongue, 



Stem glabrous below the inflorescence. 



Corolla purplish : tube not gibbous above the point of enlargement. 



1. P. Pentstemon. 

 Corolla white or pinkish ; tube gibbous above the point of 



enlargement. 2. P. Digitalis. 



Stem pubescent or puberulent. 



Stem hirsute : cauline leaves with prominent salient teeth. 3. P. hirsutus. 

 Stem puberulent : cauline leaves with appressed or obscure 



teeth. 4. P. palUdiis. 



1. P. Pentstemon (L.) Britton. Stem 3-10 dm. tall: blades of the upper 

 cauline leaves oblong-lanceolate to broadly linear, 8-17 cm. long, undulate or 

 slightly toothed: calyx-lobes ovate-lanceolate to lanceolate, 4-5 mm. long, 

 erect: corolla purplish, 16-18 mm. long: capsules 5-6 mm. long. — Common, 

 in fields and waste places. — Sum. 



2. P. Digitalis (Sweet) Nutt. Stems 3-10 dm. tall: blades of the upper 

 cauline leaves oblong, lanceolate, or ovate-lanceolate, 5-15 cm. long, entire or 

 remotely toothed: calyx-lobes lanceolate, 5-7 mm. long, spreading or recurved: 

 corolla white or pinkish, 20-30 mm. long: capsules 7-9 mm. long. — S. Occa- 

 sional, in fields and thickets, — Schists. — Sum. 



3. P. hirsutus (L.) Willd. Stems 2-7 dm. tall: blades of the upper cauline 

 leaves oblong to lanceolate, 4-10 cm. long, more or less prominently toothed: 

 calyx-lobes 5-6 mm. long, ovate to lanceolate: corolla iiurplish, 19-23 mm. 

 long : capsules 7-9 mm. long. — Common, on dry banks. — Early sum. 



4. P. pallidus Small. Stems 3-9 dm. tall: blades of the upper cauline leaves 

 oblong, lanceolate, or linear-lanceolate, 4-8 cm. long, rather remotely shallow- 

 toothed: calyx-lobes ovate, becoming triangular, about 3 mm. long: corolla 

 white or purplish, 20-25 mm. long: capsules 5-6 mm. long. — S. Rare, on 

 roadsides near Quarryville. — Schists. — Sum. 



7. PAULOWNIA Sieb. & Zuce. Trees resembling Catalpa. Leaf-blades 

 ample, entire or 3-lobed. Flowers in large panieled cymes. Calyx-lobes 5, 

 shorter than the tube. Corolla slightly 2-lipped, both lips spreading. Sta- 

 mens 4: filaments about equally adnate to the corolla. Staminodium want- 

 ing. Capsule woody, exceeding the calyx. 



1. P. tomentosa (Thunb.) Baill. Large tree: leaf -blades ovate to suborbicular, 

 1.5-4 dm. long, densely pubescent beneath, cordate, long-petioled: calyx 10-14 



