FLOWERING PLANTS AND FERNS OF ARIZONA 53 



46. Stamens more conspicuous than the small petals; h 



bipinnate, with several or numerous small leaflets; fruit 

 a flat 1-eelled pod: Subfamily Mimosoideae. 



54. Legttminosae. 



46. Stamens less conspicuous than the petals; leaves digi- 



tately compound with 3 or more wedge-shaped lea: 



fruit a turgid 5-celled capsule 56. Oxalidaceae. 



4."). Leaves simple 47 . 



47. Flowers mostly unisexual (monoecious!; pubescenc 



any) commonly of hairs affixed at the middle (mal- 

 pighiaceous) ; stamens usually 10, the anthers in 2 



whorls: Genus Ditaxis 64. Euphorbiaceae. 



47. Flowers perfect (48). 



48. Pubescence df any) of simple hairs; filaments united 

 only at base 49 . 

 49. Stamens 5: ovary 4- or 5-celled (or apparently 8- to 

 10-celled) ; leaves not glandular-punctate. 



57. Lixaceae. 



49. Stamens numerous: ovary 3-celled, or 1-celled with 



3 placentae: leaves glandular-punctate. 



76. HvPERIf ACEAE. 



48. Pubescence at least partlv of forked or stellate hairs 



50 . 



50. Leaves opposite, the blades entire: stems trailing or 



twining, woody below; fruit nutlike or winged. 

 62. Malpighiaceae. 

 50. Leaves alternate: stems not trailing or twining (51). 

 51. Stamens much more numerous than the calyx 

 lobes: anthers 1-celled: fruit of several or 

 numerous finally separate carpels, or a several- 

 celled capsule 74. Malvaceae. 



51. Stamens (fertile ones) of the same number as the 

 sepals or calyx lobes: anthers 2- or 3-celled; 

 fruit a 1-celled or 5-celled capsule. 



75. Sterculiaceae. 

 42. Filaments separate (52). 



52. Carpels more than 1, becoming separate or nearlv separate 

 fruits (53 . 

 53. Ovules 2 or more in each ovary, exceptionally solitary in 

 family Crassulaceae I 54 . 

 54. Leaves decompound: petals with long spurs: Genus Aquile- 



gia 42. Raxcxc ulaceae. 



54. Leaves simple: petals not spurred '55 . 



55. Carpels more than 5. becoming torulose and, at maturity, 

 breaking transversely into indehiscent 1 -seeded joints: 



Genus Platystemon 45. Papaveraceae. 



55. Carpels 5 or fewer, not becoming torulose or breaking 

 transversely (56). 

 56. Plants more or less succulent: carpels 3 to 5: fruits 



follicles 49. Crassulaceae. 



56. Plants not succulent; carpels 2: fruits follicles or 



capsules 50. Saxifragaceae. 



53. Ovule solitary 57 . 



57. Stems twining; flowers dioecious, small: sepals 6, in 2 series. 



44. Mexispermaceae. 

 57. Stems not twining: flowers mostly perfect: sepals rarely 

 more than 5 (58 . 

 58. Plants herbaceous: calyx of separate sepals, deciduous: 



hypanthium none 42. Raxuxcui.aceae. 



5S. Plants woody or, if herbaceous, then the calyx of more 

 or less united sepals, persistent: hypanthium usually 

 present 53. Rosaceae. 





