INDEX AND GLOSSARY 



577 



Subularia, perigynous flower of, 238. 



Succulence, in xerophytes, 176 (Fig. 

 132,) 



Suckers, organs by which parasites 

 extract nourishment from the host, 

 189 .(Fig. 140), 191 (Fig. 142), 192 

 (Fig. 143) ; shoots which appear 

 above ground, formed as adven- 

 titious buds on roots, 214. 



Suction, of water from above, 88. 



Sugar, formed in photo-synthesis, 104; 

 storage of, 109, no ; derived from 

 starch, 112. 



Sugar-beet, 541. 



Sugar-cane, 44. 



Sulphur, necessary to form proteids, 

 105 ; supply of, 107. 



Summer spores (Uredospores) , of 

 Puccinia, 443 (Figs. 777), 378. 



Sundew (Drosera), motile tentacles of , 

 131 (Fig. 91 bis) ; digestion by, 207. 



Sunflower, germination of, 12 ; 

 petiole of, 59 (Fig. 42) ; transition 

 of leaf- arrangement, 170 (Fig. 127 

 bis) ; development of epigynous 

 flower of, 238 (Fig. 188). 



Superficial placentation of ovules 

 inserted on the carpellary surface, 



255- 



Suspensor, the part of the pro- 

 embryo by which the embryo is 

 attached, 275 (Fig. 217), 280 (Fig. 

 222) ; of Selaginella, 322 (Fig. 265). 



Swelling, increase of bulk by taking up 

 water into organised substance, 5. 



Sycamore, deciduous leaves of, 162 ; 

 leaf mosaic, 169 (Fig. 127). 



Symbiosis, a mutual existence of 

 two organisms with joint physio- 

 logical action, 188, 198. 



Symbiotic conditions, 203. 



Symmetry, the proportions of a 

 shoot or root resulting from equal 

 or unequal growth round the axis 

 of construction : of root, 167 ; of 

 shoot, 1 68 ; of flower, 239 : radial 

 or actinomorphic, where develop- 

 ment is equal all round, 239 ; 

 dorsiventral or zygomorphic, where 

 there are distinct upper and lower 

 faces, 59, 172, 240 (Fig. 189) ; 

 bilateral, 172. 



Sympetalae, Dicotyledons with co- 

 herent petals (gamopetalous) , 505, 



525- 



Sympodium, a false axis built up of 

 parts which are branches of suc- 



cessively higher order, 173 (Fig. 

 13). 



Synandreae, 493, 534. 



Synapsis, an early state seen in 

 tetrad-division where the nucleus is 

 distended by nuclear sap and the 

 chromatin-bearing linin appears as 

 a tangle placed laterally, 368, 466 

 (Fig. 393, ii.). 



Syncarpous, applied to carpels when 

 united, 252 (Figs. 199, 201), 



254- 



Synergidae, two cells which, with the 

 ovum, form the egg-apparatus, and 

 co-operate with it in fertilisation, 

 260 (Fig. 206), 262 (Fig. 209). 



Syngamy, the fusion of gametes, 273, 

 461, 480. 



Tamus, 43 ; embryo of, 278 (Fig. 



220). 

 Tangles, large size and mechanical 



demands of, 136. 

 Tapetum, a layer of cells surrounding 



the spore-mother-cells in sporangia ; 



of pollen-sac, 248 (Figs. 196, 197) ; 



of Fern sporangium, 339 (Fig. 



280, L). 

 Taraxacum (Dandelion), flower of, 



538 (Figs. 444, 445) ; somatic 



parthenogenesis in, 477. 

 Targionia, structure of, 365 (Fig. 



39). 



Taxodium, 303. 

 Taxus (Yew), 302. 

 Teleutospores (or Winter Spores), of 



Puccinia, 443 (Figs. 375, 380) ; 



germination of, 446 (Fig. 381) ; 



structure of, 445. 

 Temperature, effect on germination, 



8 ; on movements in cell, 22, 24 ; 



necessary for photo-synthesis, 98, 



101 ; relation to growth, 121 



(Fig. 84 bis). 

 Tenacity, limit of, 147. 

 Tendril, 182 (Fig. 136), 185 (Fig. 



139). 

 Tensions of tissues, mutual, 142 (Fig. 



101). 

 Testa, the seed-coat developed from 



the integument, 282 (Fig. 224) : of 



Wheat, 545. 



Tetanus Bacillus, anaerobic, 460. 

 Tetra-cyclic, of gamopetalous flower 



with four cycles of parts, 233. 

 Tetracycliceae, 525, 528. 



