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cambium and the result was that, from there down on the diseased side, 

 parenchyma wood {h p) was formed which at the left ended in a medullary 

 ray {m). Still further towards the left, normal wood was produced at the 

 same time. The same difference is found in the youngest bark parenchyma 

 {r p). Because of the great radial elongation of the cells on the dropsical side 

 (W) the hard bast cords {h) are pressed out like bows and the cell rows, 

 containing calcium oxalate (o), which accompany the bast body, have also 

 been correspondingly misplaced into steeply ascending, irregular rows. At chl 

 are groups of parenchyma which have remained rich in chlorophyll. It is 

 evident that this loose structure of the tissue, rich in water, which forms 

 the swelling, has no great permanency. In dry places and with increasing 

 dryness in the air, this tissue turns brown rapidly, shrivels, collapses and 

 forms a soft, brown mass, part of which remains clinging to the wood, while 

 part sticks to the outer bark tatters which roll back in times of drought and 

 spread out, gaping, from one another. Such stems of such plants then 

 have a rusty appearance and are best excluded from cultivation. Because 

 of the ease with which such stock can be grown on strong soils, the loss 

 from the disease would be less important, if it did not attack directly the 

 potted specimens which have been budded and if the number of budded 

 plants was not considerably decreased thereby. 



I am not of the opinion, often expressed in general practice, that an 

 over-abundant feeding of the plant is to blame, but I think that an excess 

 of water makes itself felt in some places on the axis. If there should be 

 an accumulation of plastic food material here at the same time, it would 

 manifest itself preferably by an abundant cell increase. But this is not the 

 case. If the cells on the healthy and on the diseased sides are counted, only 

 an insignificant preponderance is found on the side attacked. Accordingly, 

 an abnormal cell elongation is chiefly concerned here. 



This is explained by the treatment of the Ribes stems during the 

 preparation for budding. In order to obtain slender stems, growing tall 

 rapidly, the other sprouts, produced at the sides, must be removed and 

 even the lateral branches on the young stock must be cut back. 



If now the stock is well rooted, it will grow rapidly in the greenhouse 

 and the buds, scantily present because of the earlier pruning, are still fur- 

 ther decreased by the fact that the shoots developing from them are cut 

 back or entirely removed. By cutting ofif the branches, the amount of water 

 forced up by the water pressure is increased in the main axis and manifests 

 itself in a pouch-like elongation of the younger bark cells and in the forma- 

 ion of tumor swellings which finally rupture. 



My attempts to produce dropsy by abundant watering and the rapid 

 forcing of well-rooted specimens in the greenhouse, together with a con- 

 tinued removal of the developing lateral shoots, gave very favorable results. 



The disease will be prevented if the budded stock is not forced too 

 rapidly and the sprouts from the bud are cutting back carefully, but not 



