TNDEX 



435 



Spirogyra, 290 



adnata, 109 

 Sporobolus, 274 



cryptandrus, 274 



longifoliiis, 328 

 Stachys silvalicn, 69 

 Stages in succession, 320 

 Stand of vegetation, definition of, 23 

 Staticc, 201 



gmelini, 205 



limoniam, 201 



lychnidifolia, 372 



virgata, 374 

 Staticion galloprovincialis, 374 

 Station, 21 

 Stellaria apetala, 74 



holostea, 292 



media, 88, 186 

 Stem succulents, 296 



tuber epiphytes, 296 

 Stenactis, 16 

 Steppe, Aralo-Caspian, 137 



Artemisia, 335 



Asiatic, 329 



associations, 353 



desert, 336 



fire, of Madagascar, 327 



fires, 282 



halophytic vegetation of, 202 



Podolian, 353 



Sarmatian, 137 



SHpa, 10 



therophyte, 33 



Turkestan, 202 



vegetation, 10, 329 

 Sterculiaceae, 296 

 Stereodon arcuatus, 353 

 Stereonema communities, 371 

 Stichococcus nivalis, 289 

 Stipa calamagrosiis, 10, 320 



capillata, 37, 114, 185 



caragana, 329 



spartea, 328 



steppe, 10 



tenacissima, 149, 294 

 Stipion calamagrostidis, 319, 373 

 Stratified rock communities, 188 

 Streptothrix cromogena, 244 

 Struggle for existence, 9, 11 



Suaeda, 194, 201, 308 



arcuata assn., 202 



erecta, 199 



fruticosa, 194 



maritima, 1 1 , 202 



-Kochia hirsuta assn., 11, 197, 374 

 Sub-associations, altitudinal, 344 

 Sub-district, definition of, 355 

 Sub-sector, definition of, 355 

 Subidaria, 184 

 Succession, 17, 18, 312, 317, 332 



curves, 333 



diagram of, 255, 332, 333 



due to soil formation, 255, 313 



experimental studies of, 31G 



meadow, 321 



methods of study, 332 



pioneer stages, 310 



seasonal, 12 

 Successions, deflected, 325 



primary, 325 



retrogressive, 255, 325, 326 



secondary, 326, 333 

 Succulence, cause of, 297 

 Succulents, 192, 296 



leaf, 292 



osmotic concentration of, 130 



stem, 296 

 Suction tension, of roots, 128 



related to atmospheric humidity, 

 129 

 to osmotic concentration, 129 

 Sugar, a protective substance, 88 

 SunUght, 83 



intensity, 106 

 Sulphate soils, vegetation of, 201, 202 

 Sulphates, determination of, 203 



of saline soils, 199 

 Sulphur bacteria, 203 



springs, vegetation of, 203 

 Sweetening of soil, 199 

 Swiss Alps, isotherms in, 262 



tree Limits in, 263 

 Symbiosis, mutual, 6 



nutritive, 6 

 Synchorology, 2, 343 

 Synchronology, 336 

 Synecology, 2, 81 



problems of, 81 

 Synecological units, 301 



