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selves that the perithecia are most abundant in those cases in which this devitalised 

 area has become surrounded by an enlarged and swollen margin (fig. 2, a, b) of 

 healthy bark. When the parasite attacks a small branch shoot of the last year 

 it kills it outright for some inch or two downwards ; especially is this the case 

 when the end of the shoot has been cut off (fig 2, b) ; but with the older and 

 thicker branches attacked lower down the disease gradually but surely works its 

 way through the branch, eventually cutting it quite through (fig 2, a). In this 

 case a callus above and below, as well as surrounding the canker generally, is 

 observable. Thus the distal part of the branch becomes in course of time 

 strangled by the fungus. It is useless to look for perithecia on those places in 

 which the disease has only just made its appearance. As far as I can judge, 

 the cankers made last autumn produce the perfect fungus in spring. 



In the Gardener's Chronicle, March 8, 1884, p. 312, Goethe's paper in the 

 Monatschrift des Deutsche Garten for 1880 is referred to, in which the author has 

 shown that Nectria ditissima is capable of producing the disease on Apple, Beech, 

 and Sycamore respectively. The remedy is to cut out the diseased parts and to 

 seal the wounds thus made, which would otherwise remain as vulnerable points 

 inviting the attack of the fungus-spores, by painting them over with warm coal- 

 tar. 



The injuries which branches receive by rubbing against one another may, of 

 course, open the door to the fungus spores ; but unless the latter be present, a true 

 canker is not produced by this means. 



At a recent meeting of the Scientific Committee a very curious form of 

 canker on Hawthorn was exhibited, in which the disease resembled a honey- 

 comb. Whether this was due to an insect or to another fungus, I cannot at 

 present certainly say. It, however, bears some resemblance to the cicatrix of a 

 wound caused by a fungus, Bcestelia lacerata, attacking a young twig last summer, 

 and the presence of some brownish spores in the bottom of some of the cells seems 

 to favour this view. There were also, however, found some spores very like those 

 of a Fusisporium. By further observation I hope to clear this up* — Charles B. 

 Plowvight, King's Lynn, April 7th. (The Gardeners' Chronicle, April 19th, 1884.) 



*This subsequently was found to be caused by the it;cidiospores of GymnosporanRium 



Confubuin, flow. 



