ABSTRACTS 705 



represented by species of Rhizo-pus, Penicillium, Aspergillus and Alter- 

 naria and the bacteria by B. coli, B. prodigiosus and B. subtilis. The 

 double plate method was used, one half the plate containing plain 

 agar the other half the medium plus the spice to be tested. Tests 

 were made by streaking the plate with sterile water suspensions of the 

 organisms. 



Alcoholic extracts of cinnamon, cloves and mustard showed variable 

 degrees of effectiveness. Cloves was most active; mustard not at all. 

 Rhizopus was more sensitive than Penicillium to cinnamon but less 

 so to cloves. In powder form cinnamon was more effective than 

 cloves, allspice or nutmeg. Rhizopus was not affected by cinnamon, 

 other molds and B. subtilis were highly sensitive to all spices, except 

 nutmeg; B. coli and B. prodigiosus were inhibited by allspice but 

 scarcely at all by the others. Cloves and allspice were about equally 

 effective. Cinnamic aldehyde in concentration of 1: 2000 inhibits 

 growth of all molds and bacteria; volatilization inhibits growth even 

 on spicefree half of plate. Eugenol was antiseptic for Alternaria and 

 B. subtilis only. Of the oils that of allspice was best; effective 

 against Rhizopus in 1: 5000, B. subtilis 1: 1000; it does not inhibit B. 

 coli and B. prodigiosus. 



In general mold spores were more sensitive than mycelia and both 

 more so than bacteria; B. subtilis was most sensitive among latter. 

 Spices in the amounts used in the kitchen are not good preservatives. 

 Large amounts of cinnamon, cloves and allspice do act as preservatives. 



I. J. K. 



PLANT PATHOLOGY 



Observations on Fire Blight in the Yakima Valley, Washington. J. W. 



HoTSON. Phytopath., 1916, 6, 288-292. 



Leaf infection of Bartlett pears is reported, beginning at the mar- 

 gins. Invasion of the sap wood from twig blight and an abnormal 

 number of fruit infections are also noted. — F. L. S. 



Bacteriological Blights of Barley and Certain Other Cereals. L. R. 



Jones, A. G. Johnson and C. S. Reading. Science, 1916, 44,432. 



The authors describe the causal organism for blights of barley, 

 wheat, rye, spelt, and oats. In all but the latter case the organism 

 seems to be of the same species, a monotrichous rod with a single polar 

 flagellum. It is seed-borne, which accounts for its general distribution. 

 The organism survives on infected seeds for at least two years. More 

 detailed studies will appear at a later date. — C. M. H. 



A Bacterial Disease of Western Wheat-Grass, Agropyron smithii. 



Occurrence of a New Type of Bacterial Disease in America. P. T. 



O'Gara. Phytopath., 1916, 6, 341. 



A disease of Agropyron smithii found in several places in Utah, and 

 similar to the diseases of orchard grass discussed by Rathay is de- 



