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ROYAL HORTICULTURAL SOCIETY. 



pox ; the spots gradually become confluent, extending round the 

 stem, which perishes, sometimes just as the fruit is coming to 

 maturity, exactly after the fashion of what so constantly occurs 

 in Apricots. Up to a certain time there was sufficient living 

 tissue to carry the needful supply of sap ; but the demand being 

 at length at its maximum, the fountain-head fails. 



5. A fifth form of Canker occurs occasionally, as in the Blen- 

 heim Orange, though at present I have not seen it proceed to 

 such a height as to produce serious mischief. Patches on the 

 trunk assume a fibrous appearance; but the disease does not 

 penetrate deeply, and I have found timely removal to be an effec- 

 tual remedy. How far neglect might lead to mischief in this 

 case I am unable to say. 



6. A very curious form of Canker, very different from any of 

 the preceding, occurs in some varieties, as, for instance, in the 

 Court-of-Wick Pippin. The process is in this case a very slow 

 one, and is indicated by a shortening of the branches and an 

 accompanying narrowing of the leaves. Fruit-blossoms for a time 

 are produced, impregnation takes place, and some sorry apples 

 arrive at their full development ; after a time, however, merely a 

 few leaves appear, and the whole branch perishes. 



7. I mentioned above that what I believe to be a form of 

 Canker occurs in the fruit itself, in some varieties certainly more 

 frequently than in others ; but it is not always fully developed 

 while the fruit is on the tree, though doubtless the cause was 

 antecedent to its being gathered. The fruit sometimes appears 

 sound externally ; but more frequently there are slight discoloured 

 depressions on the surface ; and when the fruit is divided, brown 

 patches are scattered through the cellular tissue, and the fruit is 

 comparatively worthless. I have frequently examined the diseased 

 spots under the microscope, and could never detect any insect ; and 

 the whole phenomena appear to me to belong to the same category 

 as ordinary Canker. 



[To be continued.] 



VI. Note on the Cultivation of the Mangrove Tree at the Gar- 

 dens of the Hoyal Botanic Society of London. By William 

 Sowerby, Assistant Secretary. 



As this curious tree has seldom been grown in England, a few 

 notes on its cultivation may interest the Members of the Horti- 

 cultural Society. 

 The " Mangrove," RMzophora mangle, is common in most 



