74(73). Stipules present: leaves usually serrate 47. Betulaceae, p. 777 



74. Stipules absent; leaves usually entire-margined 99. Cornaceae, p. 1262 



75(69). Annual herbs; sepals 4; fruit a compressed-flattened 2-celled pod with a 

 thin narrow vertical septum parallel to the direction of compression 

 64. Cruciferae, p. 962 



75. Annual or perennial herbs or shrubs, trees or vines (76) 



76(75). Plants herbaceous (include in this category woody-based vines and 

 herbs which may have slightly woody stems at base but which die 

 back to near the base every year) (77) 



76. Plants woody, never vinelike (88) 



77(76). Embryo curved, occupying the periphery of the rounded ovule and sur- 

 rounding the perisperm and/ or endosperm (78) 



77. Embryo otherwise (84) 



78(77). Each pistillate or perfect flower maturing only 1 seed (79) 



78. Each pistillate or perfect flower maturing several seeds (81 ) 



79(78). Sepals dry, scalelike, for the most part not green 



53. Amaranthaceae , p. 857 



79. Sepals herbaceous in texture (80) 



80(79). Stipules absent 52. Chenopodiaceae, p. 834 



80. Stipules present 58. Caryophyllaceae, p. 884 



81(78). Leaves alternate; flowers in terminal racemes. ...55. Phytolaccaceae, p. 870 



81. Leaves alternate or opposite; flowers not in terminal racemes (82) 



82(81). Leaves usually opposite; ovary never even slightly inferior; fruit usually 

 dehiscent by terminal valves 58. Caryophyllaceae, p. 884 



82. Leaves alternate or if opposite then the fruit opening otherwise and not un- 



commonly at least slightly inferior (83) 



83(82). Each flower with 2 bracteoles (or "sepals") at base which often enclose 



the bud; ovary 1-celled or incompletely several-celled 



57. Portiilacaceae, p. 879 



83. Flowers rarely bibracteolate; ovary completely several-celled 



56. Aizoaceae, p. 870 



84(77). Fruit a capsule of several foliiclelike parts, each part dehiscing through 

 the apical portion of the ventral suture 42. Saiiruraceae, p. 734 



84. Fruit not as in Saururaceae (85) 



85(84). Flowers unisexual; fruits capsular, 3-celled....78. Eiiphorbiaceae, p. 1082 



85. Flowers usually bisexual; fruits achenelike, indehiscent (86) 



86(85). Leaves palmately lobed or palmately or pinnately compound 



73. Rosaccae, p. 1015 



86. Leaves not palmately lobed (87) 



87(86). Stipules usually present, usually deciduous, never sheathing nor scarious; 

 placenta apical; ovule anatropous; achene usually not shiny, often 

 neither lenticular nor trigonous 50. Urticaceae, p. 788 



87. Stipules (when present) usually sheathing; placenta basal; ovule orthotropous; 



achene usually smooth and shiny, either lenticular or trigonous 



51. Polygonaceae, p. 795 



30 



