5S6 



Index 



Heterospory, 491. 

 Heterozygous, 288. 

 Homozygous, 288. 

 Horsetails, 488. 

 Horticulture, 148. 

 Host, 380. 

 Humidity, 210. 

 Humus, 221. 

 Hyacinth, water, 174. 

 Hybridization, 276. 

 Hybrids, 286; vigor of, 286. 

 Hydathodes (water pores), 175. 

 Hydnutn, 420. 

 Hydrophytes, 95, 173, 176. 

 Hypocotyl, 257. 

 Hypogynous, 239. 



Imbibition, 83. 



Indian cucumber root, 63. 



Indian pipe, 382. 



Insect pollination, 243. 



Intemodes, 116. 



Inulin, 59. 



Iris, 67. 



Irish moss, 464. 



Iron, 219. 



Irrigation, 94, 367 ; eflfects on wheat, 211. 



Jack-in-the-pulpit, 527. 

 Japanese cane, 526. 

 Jelly-making, 255. 



Kelps, 458, 461. 

 Kohl-rabi, 281. 



Labiates, 541. 



Land and water environments contrasted, 



465- 

 Landscape architecture, 148. 

 Larch, 508. 

 Latex, 58. 



Laurel, 539; family, 548. 

 Leaf, arrangement, 62; coloration, 52; 



fall, 100; mosaics, 65; parts of, 22; 



pigments, 52; position, 62; scars, 116, 



124; tissues, 24. 

 Leaves, 22, 55; effects of light on, 62; 



floating, 79; horizontal, 64; motile, 68; 

 ertical, 67 ; water 



submerged, 79 



relations of, 72. 

 Legume, 253. 

 Legume family, 537- 

 Legumes and bacteria, 397. 

 Length of day effects, 204-207 



Lenticels, 116, 126. 



Lichens, 413, 416, 443. 



Lifting of water, 160. 



Light, 203 ; and bacteria, 387 ; and growth, 

 62, 203, 204; and photosynthesis, S3', 

 and reproduction, 208; quality of, 209. 



Lignin, 56. 



Lily family, 530. 



Limiting factors, 11, 14. 



Lipase, 164. 



Liverworts, 465, 468. 



Loam, 222. 



Longevity, of plants, 143 ; of seeds, 268. 



Lotus (Nehimbo), 252. 



Lycopodiiim, 489. 



Magnesium, 216, 218. 



Magnolia, 303, 5i9- 



Mahogany, 373. 



Maltase, 164. 



Manganese, 220. 



Mango, 255. 



Mangrove, 180; seedlings of, 262. 



Manila fiber, 139. 



Maple, flow of sap in, 162 ; sugar, 349 ; wood 

 of, 154- 



Maratlia, 478. 



Marchantia, 471. 



Marquis wheat, 299. 



Mass selection, 298. 



Mechanical tissue, 136; of leaves, 30; 

 of roots, 183. 



Medullary rays (pith rays), 133, 156, 157. 



Membranes, 87. 



Mendel, experiments of, 286; law of, 292; 

 and chromosomes, 292. 



Meristem, 128. 



Mesophyll, 25, 27. 



Mesophytes, 95. 



Mesozoic vegetation, 500. 



Mesquite, 381. 



Microspora, 449. 



Middle lamella, 25, 218, 255. 



Mildews, downy, 435 ; powdery, 412. 



Mimosa, 538. 



Mineral elements, 216. 



Mint family, 541. 



Mistletoe, 380. 



Mnium, 474. 



Mold, 406; bread, 407; blue, 411; green, 

 411. 



Monocots, 130; families of, 524; stem struc- 

 ture of, 13s, 138. 



Monocotyledons, 130. 



