488 HYDROPHYLLACEAE 



II 



Stamens and style prominently exserted. 



Flowers on slender, filiform pedicels; calyx-lobes scarious in fruit. 21. P. pcdicellata. 



Flowers short-pedicellate or subsessile; calyx-lobes not scarious. 



Seeds thick, transversely corrugated; calyx-lobes oblanceolate to oval. 19. P. crenulata. 



Seeds thin, not corrugated; calyx-lobes lanceolate. 20. P. amabilis. 



Stamens and style included. 



Inflorescence corymbose; corolla 3-4 mm. long and broad; seeds thick, transversely corrugated. 



23. P. coerulea. 



Inflorescence thyrsoid; corolla about 6 mm. long and broad; seeds thin. 22. P. Anelsonii. 



Ill 



Perennials or biennials. 



Leaves with conspicuous parallel lateral veins; inflorescence usually densely congested and conspicuously 

 scorpioid. 



Foliage conspicuously silvery or white-hispid, the leaves predominantly entire. (See also varieties of 

 P. cahfornica, no. 25.) 



Leaves oval to suborbicular, the veins deeply impressed; coastal sand dunes. 



26. P. argentea. 



Leaves linear-lanceolate to oval, the veins prominent but not deeply impressed; montane or Great 

 Basin. 



Cespitose montane plants, 1-2 dm. tall; foliage and calyx hispid. 31. P. frigida. 



Slender plants of the Great Basin, 2-5 dm. tall; foliage and calyx softlv hairy. 



28. P. leucophylla. 

 Foliage green or gray, but scarcely silvery, usually some or all the leaves lobed to pinnatifid. 



Plants slender or stout, not cespitose; stems and inflorescence variously pubescent but nonglandular. 



Calyx-lobes broad, overlapping in fruit; corolla-lobes conspicuously incurved and embracing the 

 filaments and style after anthesis. 24. P. imbricata. 



Calyx-lobes narrower, not overlapping; corolla-lobes not conspicuously incurved. 



Foliage gray or hoary, the cauline leaves usually pinnatifid; pubescence hirsutulous or pilose 

 as well as bristly; calyx accrescent in fruit. 



Stems usually solitary; inflorescence virgate; corolla greenish white. 



27. P. heterophylla. 



Stems usually several, often decumbent; inflorescence of racemose or subcapitate 

 cymes; corolla lavender or white. 25. P. californica. 



Foliage green, at least the upper cauline leaves usually entire; inflorescence often purplish; 

 pubescence bristly; calyx little accrescent, glistening. 



Stems usually solitary, stout, 5-1 S dm. tall. 29. P. nemoralis. 



Stems several, slender, 1-4.5 dm. tall. 30. P. mutabilis. 



Plants cespitose; stems and inflorescence glandular-puberulent. 32. P. corymbosa. 



Leaves without conspicuous parallel lateral veins; inflorescence lax and scarcely scorpioid. 



33. P. Dalesiana. 

 Annuals. 



Inflorescence lax, scarcely scorpioid; style parted nearly to the base. 



Leaves succulent, glabrous and glaucous, all but the uppermost opposite. 35. P. raccmosa. 



Leaves herbaceous, pubescent, the upper alternate. 



Plants glandular-puberulent throughout; pedicels short; corolla pelviform to srbrn*ate. 



34. P. Pringlei. 



Plants softly hirsute and little glandular; pedicels slender; corolla broadly campanulate. 



Basal leaves linear-oblong to oval; corolla 2-4 mm. long; stamens usually included. 



36. P. Eisenii. 



Basal leaves linear-lanceolate; corolla 4-6 mm. long; stamens usually exserted. 



37. P. orogenes. 

 Inflorescence rather dense, or if lax, distinctly scorpioid. 



Corolla marcescent or tardily deciduous; style glandular-hirsute. 40. P. marccscens. 



Corolla rather promptly deciduous; style pubescent or glabrous, nonglandular. 



Plants glandular. 



Corolla pelviform; style parted about to the middle. 



Leaves oblong to ovate; calyx-lobes narrowly spatulate to obovate. 



Plants hirsute; corolla nearly white, 5-6 mm. long; coastal. 51. P. grisea. 



Plants puberulent and hirsutulous; corolla lavender, 6-8 mm. Ion".; Sicrran. 



52. P. Purpusii. 



Leaves linear to oblanceolate; calyx-lobes linear to narrowly oblanceolate. 



41. P. mohavensis. 

 Corolla campanulate; style parted nearly to the base. 45. P. verna. 



Plants variously pubescent, glandular if at all only in the inflorescence. 



Fruiting pedicels elongate and spreading or recurved in fruit; seeds 1 mm. or les.s long. 

 Leaves usually once or twice pinnatifid; seeds 10-20, 0.5-1 mm. 48. P. Douglasii. 

 Leaves usually entire, or incisely lobed; seeds 6-16, about 1 mm. 47. P. cnrvipes. 

 Fruiting pedicels erect or ascending, not elongating appreciably in fruit. 

 Seeds 1-4, 2-2.5 mm. long. 



Leaves entire; corolla violet; stamens exserted, the filaments pubescent. 



39. P. hiitnilis. 



Leaves usually pinnately lobed or pinnatifid; corolla pale blue or lavender to white; 

 stamens included, the filaments glabrous. 38. P. Breweri, 



Seeds 6-15, 1-2 mm. long. 



Cymes thyrsoid-paniculate; capsule terete, acuminate. 43. P. linearis. 



Cymes simple or few-branched; capsule flattened. 



Corolla 10-18 mm. long, 15-24 mm. broad; stamens 8-10 mm. long, the filaments 



usually hairy; coastal. 49. P. divaricata. 



Corolla 6-9 mm. lonar, 7-9 mm. broad; stamens 3-5 mm. long, the filaments papil- 

 late or glabrous; Sierra Nevada and Tehachapi ranges. 



50. P. Congdonii. 



