150a. Stamens 4 70a, in =ROSACEAE=, p. 57.

150b. Stamens 6 =CRUCIFERAE=, p. 42.

150c. Stamens numerous 43, in =RANUNCULACEAE=, p. 39.

151a. Flowers in heads or umbels --152.

151b. Flowers in slender spikes or racemes --153.

152a. Styles 2 =UMBELLIFERAE=, p. 80.

152b. Styles 5 =ARALIACEAE=, p. 80.

153a. Leaves ternately compound 43, in =RANUNCULACEAE=, p. 39.

153b. Leaves once-pinnately compound 50b, in =ROSACEAE=, p. 55.

154a. Flowers irregular --155.

154b. Flowers regular --156.

155a. Stamens 2 40b, in =SCROPHULARIACEAE=, p. 104.

155b. Stamens 5 or 10 =SAXIFRAGACEAE=, p. 49.

155c. Stamens 6 or 8 =POLYGALACEAE=, p. 65.

156a. With sheathing stipules surrounding the stem at the base of each leaf =POLYGONACEAE=, p. 24.

156b. Stipules not encircling the stem, or none --157.

157a. Petals 3 =CISTACEAE=, p. 74.

157b. Petals 4 --158.

157c. Petals 5 --161.

158a. Stamens 2 --159.

158b. Stamens 6 =CRUCIFERAE=, p. 42.

158c. Stamens 8 --160.

159a. Corolla perfectly regular; flowers in terminal cl.u.s.ters without bracts, becoming racemes; taste peppery 52a, in =CRUCIFERAE=, p. 46.

159b. Corolla slightly irregular; flowers in bracted cl.u.s.ters, or axillary; 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 cl.u.s.ters 12b, in =ONAGRACEAE=, p. 78.

161a. Leaves sword-shape, finely parallel-veined, with bristly margins 2a, in =UMBELLIFERAE=, 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; leaves princ.i.p.ally basal =SAXIFRAGACEAE=, p. 49.

164b. Flowers in rounded or flattened cl.u.s.ters; leaves princ.i.p.ally on the stem =SANTALACEAE=, p. 24.

164c. Flowers in racemes, which become elongated at maturity --165.

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

165b. Foliage p.u.b.escent =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 flowerets 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 cl.u.s.ters resembling a single flower --168.

168a. Corolla very irregular; stamens protruding =LOBELIACEAE=, p. 113.

168b. Corolla regular --169.

169a. Stamens with ordinary visible anthers; ovary 1 --170.

169b. Stamens so grown together and to the stigma as to be almost unrecognizable; ovaries 2 =ASCLEPIADACEAE=, p. 90.

170a. Petals separate =PAPAVERACEAE=, p. 41.

170b. Petals united --171.

171a. Stamens attached to the tube of the corolla =CONVOLVULACEAE=, p. 91.