ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 653 



seed corn. He rather deprecates the hot-water method. It is cheap 

 and effective, but mistakes are easily made by allowing the temperature 

 of the water to be just too high or too low, or by leaving the grains too 

 long in the hot water. For simplicity he recommends a solution of 

 sodium sulphide called " sar," in which the corn should be immersed 

 2-k hours. The results obtained from this method of killing the spores 

 were most satisfactory. 



Fungus Diseases.* — J. Ferraris gives an account of a disease of rice 

 caused by Piricularia Oryzce. The plant is attacked at the upper node 

 of the stalk and a brown patch is caused by the fungus invading and 

 destroying the cells. It penetrates the vessels and from them it invades 

 the tissues above and below the node. 



A description \ is published by the Board of Agriculture of Botrytis 

 cinerea as it affects various conifers. The results of infection experi- 

 ments are given and advice as to the best method of dealing with the 

 disease. 



J. Ritzema Bos| describes the diseased condition of Narcissus leaves 

 that were attacked by Helminthosporium gracile. The disease is known 

 in Holland as " Brand " or " burning " of the leaves. 



Dr. Ewert§ gives an account of the occurrence of Cronartium 

 ribicolum on various species of Ribes. 



J. Ritzema Bos || publishes a review of the work done during the 

 year in the phytopathological laboratory at Amsterdam. A large 

 number of harmful parasites are dealt with. A myxomycete Physarum 

 bivalve is recorded as causing the suffocation of plants of Phaseolus in a 

 green-house. A bacterial disease of turnips caused by Pseudomonas 

 ■campestris was found in North Holland, but was less virulent than in 

 1900. Work on plant diseases was also done by G-. Staes, C. J. J. van 

 Hall, and A. Ide. 



Phytopathology.^" — In connection with the Belgian Agricultural 

 Institute, Em. Marchal publishes a series of observations on the plant 

 diseases that have caused trouble during the course of the year on 

 cultivated plants. He signalises as new to the country Rhizoctonia on 

 Asparagus ; a black rot of beans due to Fusarium, and a Coryneum on 

 the leaves of the peach. 



G. Delacroix ** describes the conidial form of black rot of the vine 

 (Guignardia Bidwellii), a canker of apples caused by Splicer ops is malorum, 

 a monstrous formation of Claviceps purpurea, spots on guavas caused by 

 Glmosporium Psidii sp. n., and adds a note on the occurrence of Puccinia 

 malvacearum in France. 



Wild Plants as Nurseries of Plant-Disease.jf — A. D. Cotton draws 

 attention to the danger of allowing weeds to grow in gardens, as many 



* Malpighia, xvii. (1903) pp. 129-59 (2 pis.). 



t Jomn. Board. Agric, x. (1903) pp. 17-21 (1 pi.). 



t Zeitschr. Pflanzenkr.. xiii. (1903) pp. 87-92. § Tom. cit., pp. 92-3. 



|| Tijdschr. over Plantenziekten, viii., 202 pp. and 5 pis. See also Centralbl. Bakt., 

 x. (1903) pp. 390-7. 



«f Bull. Servi. Phytopath. Inst. Agr. de I'Etat, No. 8 (1903) 14 pp. 

 ** Bull. Soc. Mycol. France, xix. (1903) pp. 128-45 (6 figs.). 

 ft Journ. Roy. Hort. Soc., xxvii. (1903) pp. 935-42. 



Oct. 21st, 1903 2 U 



