ANALYSIS OF THE LESSONS. vi 



LESSON VIII. MoRprfOLOGY OP LEAVES AS FOLIAGE. ... p. 54. 



130. Foliage the natural state of leaves. 131. Leaves a contrivance for in- 

 creasing surface : the vast surface of a tree in leaf. 132, 133. The parts of a 

 leaf. 134. The blade. 135. Its pulp or soft part and its framework. 136. 

 The latter is wood, and forms the ribs or veins and veinlets. 137. Division and 

 use of these. 138. Venation, or mode of veining. 139. Its two kinds. 140. 

 Nettcd-veined or reticulated. 141. Parallel-veined or nerved. 142. The so- 

 called veins and nerves essentially the same thing; the latter not like tl;e 

 nerves of animals. 143. How the sort of veining of leaves answers to the num- 

 ber of cotyledons and the kind of plant. 144. Two kinds of parallel-veined leaves. 

 145, 146. Two kinds of nettcd-veincd leaves. 147. Relation of the veining to 

 the shape of the leaf. 148 - 151. Forms of leaves illustrated, as to general out- 

 line. 152. As to the base. 153. As to the apex. 



LESSON IX. MORPHOLOGY OF LEAVES AS FOLIAGE ; continued, p. 61. 



154, 155. Leaves either simple or compound. 156-162. Simple leaves il- 

 lustrated as to particular outline, or kind and degree of division. 163. Com- 

 pound leaves. 164. Leaflets. 165. Kinds of compound leaves. 166, 167. 

 The pinnate, and, 168. the palmate or digitate. 169. As to number of leaflets, 

 &c. 170, Leaflets, as to lobing, &c. 171, 172. Doubly or trebly compound 

 leaves of both sorts. 173. Peculiar forms of leaves explained, such as: 174. 

 Perfoliate: 175. Equitant: 176. Those without blade. 177. Phyllodia, or 

 flattened petioles. 178. Stipules. 179. Sheaths of Grasses ; Ligule. 



LESSON X. THE ARRANGEMENT OP LEAVES p. 71. 



181. Phyllotaxy, or arrangement of leaves on the stem : general sorts of ar- 

 rangement. 182. Leaves arise only one from the same place. 183. Clustered 

 or fascicled leaves explained. 184. Spiral arrangement of alternate leaves. 185. 

 The two-ranked arrangement. 186. The three-ranked arrangement. 187. The 

 five-ranked arrangement. 188. The fractions by which these are expressed. 

 189. The eight-ranked and the thirteen-ranked arrangements. 190. The scries 

 of these fractions, and their relations. 191. Opposite and whorled leaves. 

 192. Symmetry of leaves, &c. fixed by mathematical rule. 193. Vernation, or 

 arrangement of leaves in the bud. 194. The principal modes. 



LESSON XI. THE ARRANGEMENT OF FLOWERS ON THE STEM, 



OR INFLORESCENCE p. 76. 



195. Passage from the Organs of Vegetation to those of Fructification or Re- 

 production. 196. Inflorescence: the arrangement of flowers depends on that 

 of the leaves. 197. They arc from either terminal or axillary buds. 198. In- 

 determinate Inflorescence. 199. Its sorts of flower-clusters. 200. Flower- 

 stalks, viz. peduncles and pedicels, bracts and bractlets, &c. 201. Raceme. 

 202. Its gradation into (203) a Corymb, and that (204) into (205) an Umbel. 

 206. Centripetal order of development 207. The Spike. 208. The Hu-' 



