RHINANTHACEAE. 307 



IV. ACUMINATI. 



Inflorescence interrupted ; bracts except the lowermost shorter than the flowers ; 

 basal leaves spatulate or oblanceolate. 

 Bracts ovate to almost orbicular. 12. P. cyathophorns. 



Bracts lanceolate to linear-lanceolate. 



Calyx-lobes broadly obovate, scarious, erose, abruptly contracted into a 



very short acumination. 13. P. Watsonii. 



Calyx-lobes ovate or lanceolate, acute or gradually acuminate. 



Calyx-lobes lanceolate; plant 3-4 dm. high. 14. P. secundiAorus. 



Calyx-lobes ovate; plant 2 dm. high or less. 15. P. Fendleri. 



Inflorescence dense ; bracts large, long-acuminate, most of them exceeding the 

 flowers ; basal leaves linear or nearly so, narrower than the stem-leaves. 



16. P. angustif alius. 

 V. Glauci. 

 One species. 17. P. glauciis. 



VI. Cristati. 



Corolla-tube decidedly gibbous-ventricose ; sterile stamen densely yellow-villous ; 

 corolla purplish. 

 Basal leaf-blades obovate or spatulate or ovate, broader than the cauline leaves ; 



corolla about 1.5 cm. long. 18. P. Moffattii. 



Basal leaf-blades linear to linear-oblanceolate, usually narrower than the upper 

 cauline leaves; corolla 2-3 cm. long. 19. P. Jamesii. 



Corolla-tube funnelform, scarcely gibbous ; sterile stamen sparingly yellow-villous ; 

 corolla white. 20. P. albidus. 



VII. Harbouriani. 

 One species. 21. P. Harbourii. 



VIII. CONFERTI. 



Leaves more or less dentate. 



Calyx-lobes elongated-lanceolate, not scarious ; flowers ascending ; stem-leaves 



linear-lanceolate or linear. 22. P. gracilis. 



Calyx-lobes ovate-lanceolate, scarious-margined below and usually toothed ; 

 stem-leaves oblong-lanceolate or lanceolate. 23. P. humilis. 



Leaves entire. 



Calyx glabrous or puberulent, but not at all glandular ; its lobes with very 

 broad, erose, scarious margins and abrupt acumination. 

 Corolla over i cm. long ; upper stem-leaves broadly lanceolate, often rounded 



at the base ; plant 3 dm. high or more. 24. P. Rydbergii. 



Corolla less than i cm. long ; upper stem-leaves linear-lanceolate ; plant 

 seldom over 3 dm. high. 25. P. procerus. 



Calyx and inflorescence more or less glandular. 



Plant glabrous or nearly so. 22. P. gracilis. 



Plant decidedly puberulent. 26. P. radicosus. 



IX. Laricifolii. 

 One species. 27- P- laricifolius. 



X. Ambigui. 

 One species. 28. P. ambiguns. 



XI. Caespitosi. 



Leaf-blades obovate, spatulate or broadly oblanceolate. 



Leaves green and glabrous or slightly puberulent ; calyx-lobes oblong-lanceolate. 



29. P. suffrutescens. 

 Leaves densely grayish or whitish puberulent ; calyx-lobes lanceolate. 



30. P. caespiiosus. 

 Leaf-blades narrowly oblanceolate to linear or filiform. 



Calyx-lobes scarcely scarious-margined, entire ; inflorescence few-flowered ; 

 floral leaves like the rest. 



Leaves green and glabrate. 31- P- xylus. 



Leaves densely canescent-puberulent. 32. P. teucrioides. 



Calyx-lobes scarious-margined, dentate or erose ; inflorescence many-flowered, 



racemiform ; floral leaves reduced. 33. P. linarioides. 



