xlii 



159a. Corolla perfectly regular; flowers in terminal clusters without 

 bracts, becoming racemes; taste peppery 



52a, in CRTICIFERAE, p. 46. 



159b. Corolla slightly irregular; flowers in bracted clusters, or axil- 

 lary; taste not peppery 40b, in SCROPHULARIACEAE, p. 104. 



160a. Delicate trailing evergreen, with flowers solitary in the 

 axils and nearly or quite hidden beneath the leaves 



22b, in ERICACEAE, p. 85. 

 160b. Erect or nearly so; flowers in terminal clusters 



12b, in ONAGRACEAE, p. 78. 



161a. Leaves sword-shape, finely parallel-veined, with bristly mar- 

 gins 2a, in TTMBELLIFERAE, p. 80. 

 161b. Leaves not sword-shape 162. 



162a. Leaves toothed or lobed 163. 

 162b. Leaves entire 164. 



163a. Stems creeping 2b, in UMBELLIFERAE, p. 80. 



163b. Stems erect or nearly so SAXIFRAGACEAE, p. 49. 



164a. Flowers in open panicles; leaver principally basal 



SAXIFRAGACEAE, p. 49. 

 164b. Flowers in rounded or flattened clusters; leaves principally 



on the stem SAtfTALACEAE, p. 24. 



164c. Flowers in racemes, which become elongated at maturity 



165. 



165a. Foliage glabrous 8b, in PRIMULACEAE, p. 87: 



165b. Foliajge pubescent BORAGINACEAE, p. 93. 



166 



166a. Juice milky or colored 167. 

 166b. Juice watery, not colored 172. 



167a. Apparent flowers consisting of a few petal-like bracts, inclosing 

 a few inconspicuous flowers without petals. In some of them 

 a 3-lobed ovary with 3 styles may be seen 



EUPHORBIACEAE, p. 66. 



167b. Plants of the composite type, with several or many small flower- 

 ets closely aggregated in dense heads subtended by a calyx- 

 like involucre of small bracts 11, in COMPOSITAE, p. 115. 



167c. Flowers never aggregated in involucred clusters resembling a 

 single flower 168. 



168a. Corolla very irregular; stamens protruding 



LOBELIACEAE, p. 113. 

 168b. Corolla regular 169. 



