DISEASES OF PLANTS. 591 



Experiments are reported in which cuttings were made of diseased roots and stocks 

 grafted upon tliem, the young plant being set out to determine the development of 

 the fungus. Several varieties of apples were used in this experiment, and as a further 

 experiment inoculations were made into grafts on healthy stock. 



The author claims tliat the organism causing the crown gall gains entrance to the 

 apple seedlings in the nursery. The diseased seedlings may be detected by inspection, 

 the unusual aliundance of fibrous roots at and below the crown being an indication 

 of the presence of the disease. Care should be exercised to avoid the planting of 

 such trees, as they will succumb sooner or later to the crown gall. The experiments: 

 reported show that the disease may be readily transferred to healthy stock; hence, 

 diseased trees should not be allowed to remain among healthy ones in the orchard. 



Inoculation experiments with Nectria ditissima, R. Aderhold ( Centhl. Bakt. 

 ?t. Par., 2. Abt., 10 {1903), No. 24-35, pp. 763-766) .—Th.\H is a critical review of a 

 recent paper by Brzezinski,« which assigned, the cause of apple canker to a new 

 species of bacteria to which the name Bacterium, mali was given. The author reports 

 a number of inoculation experiments which seem to show that the true cause of 

 canker of apple trees is Nectria ditissima, and claims that additional evidence will be 

 required to establish the bacterial origin of this disease. 



Fungus enemies of the peach, plum, cherry, fig, and persimmon, F. L. 

 Stevens {North Carolina Sta. Bui. 186, pp. 33-46, figs. 10). — The more common and 

 destructive diseases of peach, plum, and cherry are described and notes given for 

 their prevention wherever definite means are known. Attention is also called to the 

 fungus diseases of the persimmon and fig, and requests made that diseased material 

 of these plants should be sent to the station. 



The relation betw^een Clasterosporiunx carpophilum and the gummosis of 

 stone fruits, R. Aderhold {Naturio. Ztschr. Land- u. Forstw., 1 {1903), No. S, pp. 

 120-133, figs. 3). — A discussion is given of the effect produced by this fungus on the 

 fruit and leaves of cherries and other stone fruits, the material being condensed 

 from a previous publication (E. S. R., 14, p. 776). 



A new group of fungi, the Bornetineae, L. Mangin and P. Viala ( Compt. 

 Rend. Acad. Sci. Paris, 136 {1903), No. 36, pp. 1699-1701).— As a result of their 

 studies on phthiriosis of the grape (E. S. R., 15, p. 165) the authors have established 

 a new grouping to include. the fungus Bornetina corium, the cause of the disease. 

 This fungus has many affinities and the special group to which it is assigned is 

 arranged provisionally between the Ustilagineai and the Basidiomycetes. 



The brunissure of the grape, L. Ravaz and L. Sicard {Compt. Rend. Acad. 

 Sci. Paris, 136 {1903), No. 31, pp. 1376-1378).— T\\e authors have claimed that 

 brunissure is the result of an overproduction of fruit, and they now report analyses 

 of sound and diseased leaves, cuttings, and roots in which comparisons are made of 

 the nitrogen, phosphoric acid, potash, lime, magnesia, and iron contents. The data 

 indicate a considerable influence on the part of the disease iu reducing the chemical 

 composition of the tissues of the plant and also the quality of the fruit. In general, 

 the diseased tissues are impoverished, their nitrogen, phosjihoric acid, and potash 

 being considerably reduced, while the lime and magnesia contents are higher. The 

 authors conclude that fruit-bearing in excess drains the plant of its fertilizing prin- 

 ciples and carbohydrates similarly to the action of parasites. 



The black rot of the grape in North Carolina and its treatment, A. W. 

 Edson [North Carolina Sta. Bid. 185, pp. 133-156, figs. 10). — The investigations on 

 which this bulletin is based were conducted in cooperation between the U. S. Depart- 

 ment of Agriculture, the State Board of Agriculture, and the North Carolina Station. 

 After briefly describing the black rot and its effect upon the grape, the author 

 describes the action of this disease as observed in North Carolina during 1902. 



«Bul. Acad. Sci. Cracovie, 1903, Mar. 



