clxvi PROCEEDINGS OF THE ROYAL HORTICULTURAL SOCIETY. 



what I desire to lay before the Committee. If the spots are those caused 

 by the Septoria in question, then the check to the development of the 

 fungus, and the absence of fruit, must be due to some efficient cause, which 

 cause I attribute to syringing with the fungicide. This being the case, 

 although it did not prevent the spots or the defoliation, would necessarily 

 stop the dissemination of the fungus, because of the absence of sporules 

 to perform this act. I conclude, therefore, that if all the fallen leaves are 

 collected and burnt, and the trees given the opportunity to recover them- 

 selves in the spring of next year (and as soon as the leaves begin to 

 unfold themselves they should be treated again once a week with a 

 diluted solution of ammoniated copper carbonate), it is highly probable 

 that they will entirely cast off the disease and recover. 



" From another source I received Cucumber leaves, spotted with the 

 large pallid blotches so familiar of late on leaves of Melons and Cucumbers, 

 as caused by the black mould Cercospora melonis. In this case also no 

 hyphae or conidia were formed ; therefore it is not possible to be quite 

 certain that the spots were caused by the Cercospora ; but there is every 

 reasonable ground to suppose that such was the case, and that from some 

 cause the development of the mould was checked, and the production of fruit 

 prevented. The correspondent in this case claims to have furnished the 

 cause of the check to the development of the mould, by the use of potash 

 in the soil, the details of which are not in my possession. It seems to me 

 that the career of the Cercospora in this instance was saddenly and 

 efficiently checked, and the cause assigned is a feasible one, which should 

 be well followed up and tested, and then made known as widely as 

 possible. 



" These may appear to be trivial matters to urge upon the Committee ; 

 but I think in both cases, if proved to be true, the results will be the 

 saving of thousands of pounds, as well as deliverance from a great source 

 of anxiety to cultivators." 



Scientific Committee, September 20, 1904. 

 Dr. M. C. Cooke, V.M.H., in the Chair, and eight members present. 



Apple and Pear Blossom, Pollination of. — In reply to Mr. Dunlop's 

 inquiry as to the advice that " no one variety of Apple should be largely 

 planted by itself," Mr. Worsley observed that such dessert Pears as 

 'Marie Louise ' require special conditions of temperature, about 70° F. in 

 a|dry place, for effective pollination. But it is not often that such perfect 

 conditions obtain when the trees are in blossom, so that Pears of that 

 variety are often regarded as "bad setters." It has been found that all 

 choicer varieties do very much better when intermingled with commoner 

 ones. 



Oat* Malformed. — Mr. Saunders, F.L.S., reported as follows upon 

 Bome stunted Oats which were shown by Mr. C. H. Hooper on 

 August 23: — " They were attacked by the stem-eel worm {Tylcnchus de- 

 vastatrix), causing them to become 'Tulip-rooted' or ' segged.' The 

 best method of exterminating this pest is to burn all the stubble-roots &c. 

 of the crop, and then to phugh the land deeply (16 or 18 inches), so as to 



