903 



Pseudomonas (Bacillus Cobb) vascu- 



larum 697 



— camp est ris 223 



Pscndotieaiza traclieipJiila 284 



Psychro-cHnic blossoms 548 



Puccinia . 53. I37 



Puccinia dispcrsa 128 



— gluinantiii 128 



— gram ill is 66, 128 



Pulteneae 134 



Pure-planting of fruit varieties. Ad- 

 vantages 295 



Pyridine 460 



Pyrites 250 



Pynts cydoiiia 51 



Pythium 227 



Pythium de Baryanuiii 222 



Oiiateniaria Perscooiiii Tul? 558 



Ouercus pedunculata So, 98 



Quinces. Layering 816 



Races, Biological 15, 128 



Radium rays. Arrestment due to 672 



Rain storms 461-62 



Rape. Effect of hail 466 



Raw-humus 241-43 



Red-rot 615 



Red-scorch of grapes 283 



Red-tan of hops 282 



Reds (le rouge) of flax 283 



— of hops 282-83 



Reductases 676 



Regeneration 887 



Relations, Climatic 134 



Reseda odoraia 126 



Reserve substances. Mobilization 106 



Resin boils 712 



— formation in Dicotyledons 716-17 



— galls on stilt roots 96 



— gathering causing wounds 780 



Resinosis, Acute 716 



— Chronic 716 



Resinosis of conifers 711-16 



Resistance. Plant power 18 



Respiration, Intra-molecular 99, 313 



Retiiwspora ericoidcs Zucc '..828 



Retrogression to juvenile form ^~~ 



Rhabditis 855 



Rhamnus 105 



Rha)iuuis Frangnla 98 



— piimila 76 



Rhi::obiiun Beijerinckii 270 



— Legumiiiosanim. Frank 11 



— radicicola 270 



Rhodanammonium 769 



Rhubarb. Acid retrogression with 



nitrogen excess 393 



— Over-fertilization 392 



Ribes 105 



Ribes aureum. Dropsy 336 



— nigrum. Gnarl formation 382 



Rice. Brusone disease 315-16 



Ricinus 100, 229 



Ricinus communis 126 



Ring barking in conifers 615 



Ring disease of hyacinth bulbs. .326-27, 451 



Ringing. See Girdling. 



Ripening. Retardation due to excess of 



nitrogen 394 



Ripening, Premature 166 



cause of blight 156 



caused by excess of heat 640 



of fruit 165-66 



of potatoes 161 



Ripening of grain, Delayed 365 



Robinia 1 54 



Robinia Pseudacacia 107 



Roentgen rays. Arrestment due to 672 



Roesleria hvpogaea 710 



Rolling 184 



Roncet 851 



Root acids. Effect of neutralization 402 



— adjustment of woody plants 78-81 



— curvature 138-42 



— cuttings S28, 886 



— decay ig6 



— decay due to marshy soil 196 



— disease of the true chestnut 219-20 



— grafts .^ ....840 



— growth 870 



— injuries 856-59 



— plants, Wilting of the foliage 365 



— removal, promoting blossom de- 



velopment ' 888 



— rot. Coffee 23 1 



Sugar cane 227-28 



— tubercles 80 



Root-ball dryness of the Ericaceae. .181-82 

 Roots. Freezing 562-66 



— Lignification 179-80 



— Outgrowths 191 



— Scurvv, Deep 367 



Girdle 368 



Knotted 367 



Surface 367 



— Secretion 139, 151, 270 



Roots, Edible.' Black-leg 220-26 



Blight 220-26 



Oxalic acid content 223 



Predisposition to disease. . .223, 225 



The threads 220-26 



See also Beets. 



Roration 44 



Ros mcllis 412 



Rosa 107 



Rosa chiuensis. Jaqu. Green blossoms. . .342 



— gallica 105 



Rose. Canker 602-6 



— Chagrination of the stems 434 



— Granulation of the stems 434 



"Rose-kings" 373 



Rosette growth 146 



— shoots 2)77 



Rost of tobacco 685 



Rot, Black, drv, of potatoes 391 



— Red 615 



— Wet 22 



Le rouge of flax 283 



Rouille blanche of tobacco 685 



Rubber plant. Tubercle disease 449-51 



Rubigo 44, 49, 53 



