1166 EXPERIMENT STATION RECORD. 



were found to be in addition to B. olex a number of other organisms. Successful 

 inoculation experiments were made with the organisms from California and Italy. 



The author failed to find resemblances between his bacteria and that described by 

 Schiff, and he concludes that no olive knots can be produced with pure cultures of 

 the spore-bearing organisms described by Schiff. 



Investigations on olive tuberculosis, R. Schiff (Centbl. Bald, [etc.], 2. AH., 

 ir, (1905), No. 7-8, pp. 200-211). — The results of the author's investigations on the 

 cause of the olive tuberculosis and studies on the biology of the organism are given, 

 a preliminary account of which has been noted elsewhere (E. S. R., 16, p. 987). 



The occurrence and prevention of gooseberry mildew, R. Ewert {Naturw. 

 Ztschr. Land u. Forstw.., 3 {1005), No. 5, pp. 200-204) .—Attention is called to the 

 occurrence of Glceosporium ribis on gooseberries, the fungus causing serious injury to 

 the plants. 



An experiment in preventing the mildew was carried on in which the shrubs were 

 sprayed with ordinary Bordeaux mixture, milk of lime, iron-free Bordeaux mixture, 

 Bordeaux mixture to which varying proportions of iron sulphate w 7 ere added, and 

 soda Bordeaux. The shrubs were sprayed twice during the season, and the effect 

 as shown on the bushes is described. The author recommends in general the spray- 

 ing of the shrubs with a 1 per cent solution of ordinary Bordeaux mixture. He also 

 recommends that resistant varieties, as far as possible, be planted, and that they be 

 stimulated to rapid growth by means of cultivation and the use of fertilizers. 



The American mildew of gooseberries, J. Ritzema Bos ( Tijdschr. Plantenziek- 

 ten, 11 {1905), pp. 170-176).— Notes are given on the gooseberry mildew {Sphserotheca 

 .mors-uvse), which has recently appeared in a number of places in Europe, where it 

 seems to be very destructive. The fungus and its effect on the host are described, 

 and suggestions given for its prevention. 



Further investigations on the bacterial disease of sesame, K. Malkoff 

 {Ghodlshen Otchet Drzhavnata Zeml. Opitna Stantzlya Sadovo, 2 {1904), pp. 149-156, 

 [German Summary], pp. 14-19, pis. J).— In continuation of a previous note (E. S. R., 

 16, p. 65) the author gives additional accounts of the biology of the organism causing 

 the wilt of sesame. 



The disease is still poorly known but may be recognized by the stems of badly 

 infested plants being wilted and affected with a sort of black rot, while those less 

 seriously attacked arc checked in their growth and as a result the crop yield is con- 

 siderably lowered. Repeated experiments in the isolation and cultivation of the 

 organism and the results of inoculation experiments are described in detail. Field 

 experiments showed that plants from early-sown seed seemed more subject to disease, 

 and moist soils also favored its development. Treating the seed grain with a 0. 1 per 

 cent solution of formalin seemed to restrict the spread of the disease in some of the 

 experiments. 



Concerning witches brooms of pear trees, F. Muth {Naturw. Ztschr. Land u. 

 Forstw., 3 {1905), No. 2, pp. 64-76, figs. 11). — A description is given of witches brooms 

 occurring on wild pear trees, the outgrowths being attributed to attacks of Exoas- 



CUS Sp. 



Witches brooms of Quercus rubra, Solereder {Naturw. Ztxchr. Land u. Forstw., 

 3 {1905), No. 1, pp. 17-23, fig. 1). — A description is given of witches brooms found 

 upon the American red oak in a garden at Erlangen, Bavaria. 



These growths have previously been reported as occurring on Quercus ilex, caused 

 by the fungus Exoascus kruchii, and on Q. lobata, due to E. quercus lobatse, but the 

 cause of the witches brooms on the red oak is thought to be an entirely distinct 

 species of fungus from those mentioned above. A list is given of trees known to be 

 subject to these growths and, so far as known, the fungi which cause them. 



In a subsequent note, by K. von Tubeuf (same journal, No. 7, pp. 309, 310, figs. 

 2), the occurrence of these growths on red oak in other localities is mentioned. 



