342 EXPERIMENT STATION RECORD. 



the removal and burning of all infected leaves or plants, and the use of fresh 

 land each season for celery. 



Cotton wilt and root knot, W. W. Gilbert iU. 8. Dept. Agr. Farmers' Bui. 

 625 (lOl/f), pp. 21, figs. 15). — Popular descriptions are given of the cotton wilt 

 due to Fusarium va»infectum and the root knot caused by Eeterodera radici- 

 cola. For their control the author recommends thorough rotation of crops and 

 the growing of varieties that are known to be resistant to these pests. 



Downy mildew of cucumbers, G. E. Stone (Massachusetts Sta. C'irc. 40 

 (1914), pp. 2, fig. 1). — A description Is given of the downy mildew of cucumbers 

 due to Peronoplasmopara cuhcnsis, which is said to be one of the most trouble- 

 some pests in cucumber culture under glass. 



The author states that the disease is not necessarily difficult to hold in check 

 if proper attention is paid to the moisture of the house. In no case should 

 moisture be allowed to remain on the foliage for more than 2 or 3 hours, and 

 even during the warm months steam should occasionally be turned on so as to 

 dry out the house and change the air. 



The control of onion smut, G. E. Stone (Massachusetts Sta. Circ. 41 (1914), 

 PP- 4< flff^- 4)- — The author states that positive results on the control of onion 

 smut have been obtained by applying sulphur at the rate of 100 lbs. per acre 

 thoroughly mixed with 50 lbs. of air-slaked lime in the drills, or by the appli- 

 cation of ground lime at the rate of from 75 to 100 bu. per acre. The best re- 

 sults, however, have been obtained by the use of formalin at the rate of 1 oz. 

 to 1 gal. of water, or in even weaker solutions, the formalin solution being ap- 

 plied to the row as the seed is planted. A device for the application of the 

 formalin is fully described. 



Some diseases of the potato. — III, Black scab or warty disease, Ethel M. 

 DoiDOE (Agr. Jour. Union So. Africa, 8 (1914), ^o. 1, pp. 50-55, pi 1, figs. 3). — 

 This is a brief descriptive discussion of the disease known as potato canker, etc., 

 due to Synchitrium endohioticum and noted at several points in Europe and 

 America, but not in South Africa. A map of England showing infected areas is 

 given. Varieties claimed to be more or less resistant, and also the soil treat- 

 ment with 1 per cent formalin recommended by Eriksson (E. S. R., 31, p. 82), 

 are mentioned. 



Leaf blotch in the potato, A. S. Hobne (Jour. Roy. Hort. Soc. [London], 39 

 (1914), No. 3, pp. 595-606, pis. 6, fig. 1). — The author reports in considerable 

 detail on a continuation of investigations previously noted (E. S. R., 25, p. 750) 

 as carried out on leaf blotch in the President potato. 



It is stated that crops of this variety produced in light sandy soil at Wisley, 

 in 1912 and 1913, were very small. A considerable proportion of defective 

 plants occurred, some plants growing only a few inches in height and bearing 

 only two or three small tubers. Both good and bad plants flowered at "Wisley, 

 but did not produce seed. Macrosporium soJani was not noted at this place. 

 Tubers from diseased plants generally transmitted the defect, but one such 

 tuber placed in different environment produced a plant with good foliage. 

 Both good and bad plants were produced at Wisley from tubers of medium 

 size taken from different localities. The tubers were very variable in shape, 

 size, eye characters, texture, and kind of skin, but occurrence of affected plants 

 did not appear to be in any way related to these characters or to injuries suf- 

 fered by the tubers or shoots. 



Leaf roll of potatoes and related diseases, R. Schandeb (Fiihling's Landw. 

 Ztg., 63 (1914), No. 7, pp. 225-243) .—This is a brief general summary of dif- 

 ferent diseases usually characterized more or less by curling of the leaves, with 

 a discussion of possible remedial measures therefor, such as breeding, soil selec- 

 tion and improvement, drainage, cultivation, and spacing. 



