98 Journal of Agricultural Research voi. vi, no. 2 



portant, which effect a contact of diseased parts with healthy parts, are 

 to be recognized as carriers. 



In efforts to control the disease quarantine measures have been passed, 

 thus preventing its further introduction from foreign localities and from 

 any one of the Gulf States to any other of them. The use of spray mix- 

 tures indicates that they are not to be regarded as remedial measures of 

 appreciable value in canker control; nor will their use protect healthy 

 trees adjacent to diseased ones from infection. 



Successful eradication seems possible, but only when the work of de- 

 struction of diseased trees is thoroughly done, with the observance of 

 proper sanitary precautions. 



LITERATURE CITED 

 (i) Berger, E. W. 



1914. Citrus canker — History. In Fla. Grower, v. 11, no. 7, p. 14-15. 

 (2) Stevens, H. E., and Stirling, Frank. 



1914. Citrus canker — II. Fla. Agr. Exp. Sta. Bui. 124, p. 27-53, fig- 7~i4- 



(3) Comes, Orazio. 



1913. Delia resistenza dei frumenti alle ruggini. Stato attuale della quistione 



e prowedimenti. In Atti R. 1st. Incorag. Napoli, s. 6, v. 64, 1912, 

 p. 421-441. Letteratura e note, p. 437-440. Abstract in Intemat. 

 Inst. Agr. [Rome], Mo. Bui. Agr. Intel, and Plant Diseases, year 4 

 no. 7, p. 117-119. 



(4) Crabiix, C. H., and ReEd, H. S. 



1915. Convenient methods for demonstrating the biochemical activity of 



microorganisms, with special reference to the production and activity 

 of enzymes. In Biochem. Bui., v. 4, no. 13, p. 30-44, pi. i. 



(5) Edgerton, C. W. 



1914. Citrus canker. La. Agr. Exp. Sta. Bui. 150, 10 p. 



(6) Hasse, Clara H. 



1915. Pseudomonas citri, the cause of citrus canker. A preliminary report. 



In Jour. Agr. Research, v. 4, no. i, p. 97-100, pi. 9-10. 



(7) Hawkins, L. A. 



1915. Some effects of the brown-rot fimgus upon the composition of the peach. 

 In Amer. Jour. Bot., v. 2, no. 2, p. 71-81. Literature cited, p. 80-81. 



(8) Joint Rubber iNSLrtATioN Committee. 



1914. Tentative specifications and analytical procedure for 30^ Hevea 

 rubber insulating compoimd. Preliminary report of the joint rubber 

 insulation committee appointed by a group of manufacturers and 

 users of rubber compounds, 19x1-1914. /« Jour. Indus, and Engin. 

 Chem., V. 6, no. i, p. 75-82, illus. 



(9) Koch, W. 



1909. Methods for the quantitative chemical analysis of animal tissues. I. 

 General principles. In Jour. Amer. Chem. Soc, v. 31, no. 12, p. 

 1329-1335. 



(10) and Mann, S. A. 



1909. Methods for the quantitative chemical analysis of animal tissues. II. 

 Collection and preservation of material. In Jour. Amer. Chem. Soc, 

 v. 31, no. 12, p. 1335-1341. 



