1 8 FAMILY KEY 



I. Style i, 3-lobed at apex; capsule 3-valved, 3-celled; placentae usually 



axial. POLEMONIACEAE (p. 183) 



II. Styles 2, often more or less united at base, sometimes united nearly to 

 apex; capsule 2-valved, i-celled; placentae 2, parietal. 



Nemophila in HYDROPHYLLACEAE (p. 185) 

 GG. Ovary inferior or mainly so. 

 J. Flowers in terminal cymes; stamens 3; leaves 3-5-foliolate. 



Valeriana in VALERIANACEAE (p. 214) 

 JJ. Flowers in heads; stamens 4-5; leaves various. COMPOSITACEAE (p. 218) 



GROUP 10 Dicotyledonous herbs with simple leaves in 

 whorls of 3 or more scattered along the stem 



A. Stem square; leaves 4-8 in a whorl; fruit very deeply 2-lobed or separating into 



2 distinct carpels. Galium in RUBIACEAE (p. 211) 



AA. Either the stem terete or else the leaves in whorls of 2-3; fruit not deeply lobed, 



not separating into distinct carpels. 

 B. Plants growing in water; stem simple; stamen i. 



Hippuris in HALORAGIDACEAE (p. 162) 

 BB. Plants of ordinary dry soil; stem normally not simple; stamens 2-10 (in 



Euphorbia only i). 



C. Leaves terete, 8-16 in a whorl; styles 5. Spergula in CARYOPHYLLACEAE (p. 90) 

 CC. Leaves flat, 2-6 in a whorl; styles i or 3. 



D. Leaves 4-6 in a whorl, 2.5 cm. or less long, spatulate or oblanceolate; stems 

 prostrate; styles 3. AIZOACEAE (p. 86) 



DD. Leaves 2-4 in a whorl, often longer, blade often widest below its middle; 



stems not prostrate (except sometimes in Euphorbia). 

 E. Sepals 2-3, distinct; petals 4 or 6, distinct. 



Platystigma in PAPAVERACEAE (p. 104) 

 EE. Sepals either none or 4-8 and all somewhat united into i piece; petals 



none or united into i piece. 

 F. Corolla present; stamens 4-8. 

 G. Leaves in several whorls along an elongated stem. 



SCROPHULARIACEAE (p. 198) 



GG. Leaves either not in whorls or the whorls merely basal or terminal. 



PRIMULACEAE (p. 175) 



FF. Corolla none; stamens i or 2 or 3 or 9. 

 H. Calyx present; stamens more than i; fruit an akene, 3-angled. 



POLYGONACEAE (p. 79) 



HH. Calyx none; stamen i; fruit a capsule, 3-celled, terete or nearly 

 so. Euphorbia in EUPHORBIACEAE (p. 145) 



GROUP 11 Apetalous or polypetalous dicotyledonous 

 herbs with opposite simple leaves and superior ovary 



A. Petals none. 



B. Leaves 2-3-pinnatifid; leaf segments linear to lanceolate; pistils more than i; 

 fruit akenes with plumose tails 2.5-3.7 cm. long. 



Clematis in RANUNCULACEAE (p. 95) 



