Part 1, 1905] 



CRASSUI.ACBAB 



61 



Petals yellow. 



I^eaves not ciliate. 



lyeaves linear-lanceolate, scarious. 

 lyeaves oblong-lanceolate, green. 

 Leaves, at least the lower ones, ciliate. 

 Petal white, tinged with pink. 



** Leaves spatulate to obovate, narrowed at the base. 

 Annual species. 



Flowers close together on the cyme -branches. 

 Flowers distant on the long leafy cyme -branches. 

 Perennial species. 



Shrubby species with relatively broad leaves. 

 Petals white. 



Flowers pedicelled. 

 Flowers sessile or subsessile. 

 Bark granular or tuberculate. 



Carpels 6 to 8 ; petals acute, keeled. 

 Carpels 5 ; petals mucronate below the apex. 

 Bark puberulent, not granular nor tuberculate. 

 Petals yellow, orange or red. 

 Petals purplish-red. 

 Petals yellow to orange. 

 Flowers pedicelled. 

 Flowers nodding. 

 Flowers not nodding. 

 Flowers sessile or subsessile. 

 Leaves pale and glaucous. 

 Leaves bright green, not glaucous. 

 Leaves distinctly retuse at the apex. 

 Leaves not retuse. 



Leaves broad, obliquely truncate at the apex. 

 Leaves narrow, acutish. 

 Leaves obovate. 

 Leaves oblanceolate. 

 Decumbent or tufted species with erect or ascending flowering stems. 

 Leaves, or some of them, verticillate in 3's. 

 Leaves alternate or rarely opposite. 

 Flowers white to purple . 



Flowers slender-pedicelled. 



Leaves with a filiform terminal appendage ; petals white 



below, reddish above. 

 Leaves not appendaged ; petals purple. 

 Flowers sessile or short-pedicelled. 



Plants pubescent or puberulent-granular, at least above. 

 Petals 5 mm. long ; basal leaves spatulate, hirsute. 

 Petals 6-7 mm. long ; basal leaves obovate, glabrous 

 or papillose. 



— Leaves tlirgid, the basal ones smooth. 



- Leaves flattish, at least the basal ones papillose. 



Plant papillose all over ; sepals 3 mm. long. 

 Sepals not papillose, 5 mm. long. 

 Plants glabrous. 



Calyx -segments acute to acuminate ; petals white. 

 Calyx-segments obtuse. 



Petals obtuse or apiculate. 



Petals purple ; carpels widely divergent ; Mex- 

 ican species. 

 Petals white, tinged with rose ; carpels ascend- 

 ing ; Alleghenian species. 

 Petals acute ; Texan and Mexican species. 



Flowers yellow. 

 Flowers cymose. 



Follicles ascending, or nearly erect. 



Basal leaves spatulate ; plants glaucous or white-pru- 

 inose. 

 Plant densely white-pruinose ; basal leave sbroadly 



spatulate . 

 Plants pale-green or glaucous or somewhat prui- 

 nose ; basal leayes spatulate. 

 Petals 6-7 mm. long ; leaf -margins slightly 



papillose. 

 Petals 8-10 mm. long; leaves with a line of 

 pits near the margin on the under side. 

 Basal leaves obovate -orbicular ; plant not glaucous. 

 Follicles widely divergent. 



Branches of the cyme short, mostly simple ; leaves, 



at least those of sterile shoots, opposite. 

 Branches of the cyme long, forked ; leaves alternate. 

 Biennial. 



30. 5. Douglasii. 



31. S. s has tense. 



32. S. ciliosum. 

 2)^. S. CockerelUi. 



34. S. naviculare, 



35. S.jaliscanwm. 



36. 5". tortuosum. 



37. S. retusum. 



38. 5. tuberculatum. 



39. ^. Conzattii. 



40. S. oxypetalum. 



41. S. Botteri. 



42. 5". Nelsoni. 



43. 5". Palmeri. 



44. 5". Purpusi. 



45. ^S". dendroideuni 



46. 5. confusum. 



47. 5. praealtum. 



48. 5. ternaium. 



49. S . filiferum . 



50. 5. longipes. 



51. S. Lumholtzii. 



52. S. JVootoni. 



52>. S . puberulum. . 



54. 5. Griffiihsii. 



55. ^. californicwni 



h^. S. madrense 



57. 5. Nevii. 



58. S. Wrighiii. 



59. S . pruinosum . 



60. S. anomatuin. 



61. i\ spathulifoliuni . 



62. S . yosemitense . 



63. 5. diver gens. 



64. S. Leibergii. 



