370 
Dahlia, thickened roots of, 33, *34. 
Daily movements of leaves, 108, 
*109, *110. 
Dandelion, *55. 
Datura, stigma of, *164. 
Deciduous, 141. 
Defenses against animals, 122-126*, 
Definite annual growth, 54. 
Dehiscent fruits, 185, *186, *187, 
#194, 
Deliquescent trunk, 53. 
Dentate, App. I, #357. 
Descent of water, *70, 80, 81. 
Desmids, *219. 
Destruction of plants, 203. 
Determinate inflorescence, App. I, 
361. 
Deutzia leaves, *108, *109. 
Diadelphous, 153, *155. 
Diagrams, floral, *156, *157. 
Diatoms, *219, 235-237. 
Dichogamy, *175, 176. 
Dicotyledonous plants, 28, 211, 
Dicotyledonous stem, annual, gross 
structure of, 67, *68. 
Dicotyledonous stem, cross-section 
of, *68, *70, *72, *73. 
Dicotyledonous stem, minute struc- 
ture of, *69, 
Dicotyledonous stem, rise of water 
in, 78-80, *81. 
.Dimorphous flowers, *178. 
Dicecious, *149. 
Discharge of pollen, *162. 
Diseases, varieties resistant to, 322, 
323. 
Dispersal of seeds, 191-199. 
Distinct, 151. 
Distribution of material in mono- 
cotyledonous stems, 66, 67. 
ESSENTIALS OF BOTANY 
Division of labor, 304-308. 
Dock fruit, study of, 183, 184. 
Dodder, 32, *33, 
Dormant buds, 95. 
Double flowers, 160. 
Drosera, *119, #120, *121. 
Drought, endurance of, 115. 
Drought-plants, 114. 
Dry fruits, 187. 
Duct, *69, *70, 78. 
Dyes, 339. 
Earliest plants, 255, 256. 
Ecology, 2, 105-125*, 168-180*, 
191-199*. 
Egg, osmosis in, 45, *46. 
Egg-cell, 165, *166. 
Elaters, 288, 291. 
Elliptical, App. I, *355. 
Elm bud, *92. 
Elm fruit, *187. 
Elm leaf, 97, 98. 
Elm twig, *92. 
Emarginate, App. I, *356. 
Embryo, 5, 14. 
Embryo sac, *166. 
Endogperm, *13, 14, *17, 
‘Energy, source of, in plants, 140, 
141, 
Epidermis of root, *36, *37. 
Epidermis, uses of, 131, 132. 
Epigynous, *156. 
Epipetalous, 155, *156. 
Equisetum, type study, 287-290*. 
Essential organs, *148. 
Euphorbia splendens, *125. 
Evergreen, 141. 
Evolutionary history of plants, 295- 
305*. 
Excretion, 44. 
