682 



BOTANY OF THE LIVING PLANT 



Land vegetation, introductory to, 



454 (Chap. xxix.). 

 Lantana, straggling habit of, 214 



(Fig. 143, hi.) ; spread by birds in 



Ceylon, 331, 345. 

 Lastraea, see Dryopteris. 

 Latent period, 334. 

 Lateral geotropism, of twining stems, 



215. 



Lateral roots, origin of, 90 (Fig. 



65)- 

 Latex cells, of Euphorbiaceae, 54. 



Latex vessels, of Cichoriaceae, 54. 



Lathraea, parasitism of, 226. 



Lathyrus aphaca, correlation in leaf, 

 219 (Fig. 148). 



Laticiferous tissues, 53 (Fig. 32). 



Latticed girders, 180. 



Layering, 158 (Fig. 93). 



Leaf, definition of, 69 ; structure of, 

 (Chap, v.) ; structure suited to 

 function, 80 ; phototropic response 

 159 ; arrangement, whorled or 

 cyclic, 201 ; alternate, 202 ; fall, 

 80 (Fig. 55), 153 ; symmetry of, 

 200 ; rolling of, 210 ; branch- 

 system of, 348 ; origin of, 352. 



Leaf-mosaic, the fitting of the leaves 

 together, so as fully to occupy 

 space exposed to light without 

 overlapping, 201 (Figs. 134, 137, 



138). 

 Leaf-mould, source of saprophytic 



nourishment, 221. 

 Leaf-scar, surface of separation of 



leaf from axis, 13 (Fig. 6), 78 (Fig. 



55). 

 Leaf-trace, in Ferns, 486. 



Legume or pod, a separate carpel, 

 splitting along both margins and 

 midrib, and containing several 

 seeds, 321, 323, 635. 



" Legumes," analysis of, 655. 



Leguminales, 635. 



Leguminosae, climbing habit of, 213 ; 

 root-nodule of, 235 ; flowers of, 

 636 (Fig. 489). 



Lemanea, 387. 



Lemna, movement of chloroplasts in, 

 78 (Fig. 54). 



Lenticels, breathing pores through 

 corky covering of a stem or root, 

 13 (Fig. 6), 66 (Fig. 44), 80 (Fig. 



55)- 

 Lentil (Ervum lens), analysis of, 655 ; 



origin of, 656. 



Lepidocarpon, seed-like organ of, 521. 



Lepidodendron, 511. 



Leptom, of Mosses, 464 (Fig. 358). 



Leptothrix, 451. 



Lesser Celandine, delayed germina- 

 tion, 140. 



Lettuce (Lactuca scariola), high 

 water-content of, 95 ; analysis of, 



655- 

 Leucobryum, 465. 



Leucojum, 608. 



Leucoplasts, or starch-forming cor- 

 puscles, 124 (Figs. 81, 85). 



Lianes, woody climbers of large size, 

 213. 



Liberation of oxygen in photosyn- 

 thesis, 121. 



Lichens, symbiosis of, 427 (Figs. 326, 

 327), 446 ; Myxophyceae a con- 

 stituent of, 376. 



Life, indications of, 30. 



Life-cycle of Algae, 390 ; of Flower- 

 ing Plants, 335 (Fig. 257) ; of 

 Ferns, 506 (Fig. 400) ; of Bryo- 

 phytes, 456, 544. 



Light, necessary for photo-synthesis, 

 108 ; local effect of, 117 (Fig. 78) ; 

 source of energy, 114; retarding 

 influence on growth, 146 ; effect 

 on growing organs, 158 ; on ger- 

 mination, 140. 



Light-rays absorbed by chlorophyll, 

 116 (Fig. 77). 



Lignified walls, of woody character, 

 24. 



Lignin, 124. 



Ligulatae, those Lycopods which 

 have a ligule, 512. 



Ligulate florets, of Compositae, 649, 

 651 (Fig. 480). 



Ligule of Selaginella, 515 (Figs. 407- 

 409) ; of Lychnis, 621 (Fig. 

 470). 



Liguliflorae, 651. 



Liliaceae, meristic differences in, 265, 

 607. 



Liliales, 606 (Fig. 455). 



Lilium, origin of embryo-sac in, 297 ; 

 fertilisation in, 307 (Fig. 228), 607 

 (Fig. 455). 



Lily, bulbils of, 245 ; syncarpous 

 pistil of, 289 (Figs. 209, 211) ; 

 stigma of, 292 ; of the Valley, 608. 



Lily Disease, 395. 



Lime Tree, products of cambium of, 

 59 (Fig. 38) ; secondary thickening 

 of, 62 (Figs. 40, 41) ; leaf-mosaic 

 of, 206 (Fig. 138). 



Lime (calcium oxide), 97 ; in plant 

 distribution, 112 ; in soil reaction, 



113. 



Limit of elasticity, 178 ; measured 



by the greatest burden per unit 

 of transverse section which can be 



