252 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



fruit bodies are to be found on the cankers, and the freshly cankered 

 tissues are watery, not dry. A large percentage of the cankers are active 

 but for one season, not, as in some other cankers, spreading from year to 

 year. The effect of the disease upon the tree as the bark is killed is similar 

 to that produced by partial or complete girdling, causing a check to the 

 flow of food to the leaves from the roots. The fohage never fully expands, 

 but remains undersized and curled, and of a pale-green or grey colour. As 

 the canker advances, the leaves often die and dry up on the branches. 

 Trees that manage to survive have scanty foliage, blossom profusely, and 

 frequently set a heavy crop of fruit, which falls prematurely. Viscid 

 milky drops exude from the canker on moist, cloudy days, and these drops 

 contain large numbers of bacteria, the organisms which are the cause of 

 the disease. These bacteria, known as Bacillus amylovorus (Burr.) de 

 Toni, also swarm in the diseased tissues of the apple. The same bacillus 

 causes the well-known " fire blight " of the pear and the " twig blight " 

 of the apple. The trees become infected through weak shoots (" water 

 sprouts "), to which the bacilli may be conveyed by insects, by means of 

 the pruning-knife, through wounds or bruises on the branches caused by 

 cultivation, gnawing animals, &c., and by other agents causing wounds. 

 The means of treatment that promise the best results appear to be to cut 

 out the cankers, and to swab out the wound with a weak solution of corro- 

 sive sublimate or 3 per cent, solution of copper sulphate, and, when dry, 

 to paint over thoroughly with some heavy lead paint. Preventive measures 

 are the avoidance of bruisinsr the bark, destruction of dead branches and 

 trees, cutting out and burning every trace of twig blight as soon as 

 detected, painting the wounds, keeping the trees free from water sprouts 

 during summer, avoidance of the excessive use of nitrogenous manures, and 

 planting of trees with open branching habit. The disease has been destruc- 

 tive in the apple-growing regions of the United States, Canada, and prob- 

 ably England. Certain varieties appear much more susceptible to the 

 disease than others ; ' Baldwin ' is particularly liable, * Ben Davis,' ' Mann,' 

 ' Hubbardston,' ' Fall Pippin,' ' Stark,' and ' Greening ' all seem suscep- 

 tible, while the most resistant appear to be ' Wolf River,' ' Talman Sweet,' 

 ' Pewaukee,' ' Red Astrachan,' ' Tetofsky,' ' Grimes's Golden,' * ^Yine Sap,' 

 ' Fameuse.' A series of capital illustrations from photographs enhance the 

 value of this excellent bulletin. — F. J. C. 



Apple, Nomenclatupe of. By W. H. Ragan [U.S.A. Dep. Agr. 

 {Bur. PI. Lid.), Bull. 56 ; Jan. 1905). — A catalogue of all the varieties of 

 apple referred to in American literature from 180i to 190-1, with notes 

 on their place of origin, and descriptions indicating form, size, colour, 

 texture and colour of flesh, flavour, use, season, and quality, as well as 

 references to literature. About 360 octavo pages of small type are filled 

 v.'ith the names and brief descriptions of varieties, each occupjing a single 

 line, and somewhere near 16,000 names are mentioned, many of which 

 are synonymous, and these are indicated by difference in type. — F. J. C. 



Apple Spraying.— By Chas. S. Crandall (U.S.A. Exp. Stu. Illinois, 

 Bull. 106 ; 9 plates\ — The relative merits of liquid and dust applications 

 for the repression of injuri::u3 insects and fungi form the subject of this 



