DISEASES OF PLANTS. 373 



Elevator inspection, which is inchided as part of the (hities of the inspector of noxious 

 weeds, is briefly reported upon. In the main it was found that the elevators through- 

 out the Northwest Territories are careful in cleaning and distributing their seed. 

 Some instances were found in which large amounts of noxious weed seed were pres- 

 ent in the screenings from wheat and oats. 



DISEASES OF PLANTS. 



Immunity to plant diseases secured by the absorption of fungicides, E. Mar- 

 ch al (/h*;. Agr. Gemhloux, 13 {1903), No. 12, pp. 524-527). — On account of the 

 apparent success which certain investigators had reported on securing the immunity 

 of potatoes to the downy mildew, the author investigated the possibility of securing 

 immunity to lettuce and various cereals against some of their more destructive 

 parasites. 



In the lettuce experiments young seedlings were removed to culture media con- 

 taining from 6 to 8 parts of copper sulphate in 10,000, and after growing in this for 

 some time were inoculated with spores of Bremia lactuca\ The plants seemed to 

 show considerable resistance and the immunity seemed to be in proportion to the 

 strength of the solution. Where grown in solutions containing 1 part in 10,000 or 

 less of the fungicide no predisposition to immunity was shown. 



The experiments with cereals were for the protection against rusts and mildew. 

 In these experiments no immunity was secured. The author believes that immunity 

 against such fungi as the downy mildews may to some extent be secured by the 

 absorption of fungicides by the growing plant. 



Parasitic fungi, G. P. Clinton ( Connecticut State Bd. Agr. Rpt. 1902, j)p. 253-265). — 

 In an address the author popularly describes parasitic fungi and their methods of 

 attacking numerous economic plants. Suggestions are given for the control of para- 

 sitic fungi, selection, pruning, and treatment for fungicides being described. In con- 

 clusion, the author briefly describes bacteria, rusts, smuts, downy mildew, and 

 powdery mildew as causes of plant diseases. 



Pathological plant anatomy, E. KItster {PathoJogische Pflanzenanatomie. .Tena: 

 Gusfav Fischer, 1903, pp. VII -^312, figs. 121).— This is an outline study of the 

 anatomy of pathological plant tissues in which the author treats of the modified 

 structures produced by various factors that induce departures from normal. It is an 

 outgrowth of a previous publication by the author on the anatomy of plant galls. 



A study of some diseases of cereals in Mexico, S. Boxansea {Mem. y Rev. Soc. 

 Cieni. "Antonio Alzate,''' 18 {1903), No. 3, pp. 125-136). — A list is given of the various 

 cryptogamic parasites of cultivated cereals in Mexico. This includes various smuts, 

 rusts, etc., and suggestions are given for their prevention so far as any means are 

 known. 



A cotton disease at Montserrat, H. H. Ballou {Agr. News [Barbados'], 2 {1903), 

 No. 38, p. 309).^ A l)rief description is given of a disease of cotton caused by a leaf- 

 gall mite, Phytoplus sp. This pest has destroyed a considerable amount of cotton and 

 so far as the author has been able to determine it has not previously been reported 

 upon this plant. He states that all ratoon cotton should be destroyed and active 

 measures taken for the destruction of the mite, as it threatens to become one of the 

 most serious pests of the cotton plant. 



Experiments in the prevention of oat smut, T. Johnson {Econ. Proc. Roy. 

 Dublin Nor., ; {1902), pp. 119-131; <d>.^. in Bot. CcntbL, 92 {1903), No. 20, p. 465).— 

 A report is given «of tests of formalin, hot water, sodium sulphid, and potassium 

 sulphid for the ])revention of oat smut in Ireland. Based upon the results obtained, 

 the author recommends soaking the seed before sowing in solutions of potassium 

 sulphid or sodium sulphid for simplicity of procedure and efficiency of treatment. 



