572 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



management of Palms, Ferns, Dracjenas, Camellias, Azaleas, and other 

 plants commonly grown as window- plants or in rooms. — /. P, 



Plectranthus keniensis. By Spencer Le M. Moore {Journ. Bot. 

 464, p. 264 ; 8/1901). — Description of a new species near P. flacciclus, 

 from Mount Kenia. — G. S. B. 



Poisonous Plants. By V. K. Cheshimt {U.S.A. Dep. Agr. 1900, 

 p. 805). — A history of the investigation of the losses of stock on ranches 

 caused by poisonous plants, especially of the genera Cicitta, Delphinium, 

 and Zygadenus. — C. W. D. 



Polyactis cinerea, Destruction of.— M. Beauverie {Bev. Hort. 



Beige, t. xxvii. p. 172, August 1901) has succeeded in rendering plants 

 immune from attacks of this fungus, e.g. Begonias, by growing them in 

 earth which has been treated with the liquids secreted in the culture of 

 Polyactis [Botrytis). This result is interesting as running parallel with 

 the serum-therapeutics in man, and is important to horticulturists as 

 furnishing the means of preserving plants from this very common 

 disease. — G. H. 



Pomology {U.S.A. St. Bd. Connec., 34th Report, 1900).— J. H. 

 Hale states the lessons in Pomology learnt in 1899 and 1900, showing 

 the importance of the fruit industry. The results and lessons of the 

 "great freeze" in February 1899, also under conditions of excessive 

 drought, were the stimulation of better tillage and better care all over 

 the country. " Some of the largest and most beautiful Peaches, Pears, 

 and Apples have been grown, probably the finest Peaches ever grown in 

 Connecticut, were produced this year in those orchards where careful 

 attention had been given to culture." — M. C. C. 



Poplar Plantations in Sweden. By W. E. D. {Gard. Chnm. 



No. 753, p. 356 ; 1/6/1901). — An account is given of the different species 

 whose wood is used in the manufacture of matches, and the best methods 

 of their cultivation for this purpose. — G. S. S. 



Potamogeton natans. By G. M. Holferty {Bot. Gaz. vol. xxxi. 

 p. 339, No. 1 ; 2 pi. and 1 fig.). — Describes the ovule and embryo in 

 formation. — G. H. 



Potato Crop, Causes of the Failure in 1897 {U.S.A. Exp. St. 

 Hatch, Report 10, 1898). — The causes are concluded to be the excessive 

 rainfall of the previous season. The small yield and large amount of 

 rotting were easily to be attributed to this source. The Phytophthora 

 made its appearance early in August, and developed very extensively 

 during the month. — M. C. C. 



Potato Diseases and their Treatment. By B. T. Galloway, Chief 



of the Div. of Veg. Phys. and Path, of the U.S. Dep. of Agric. (Bidl. 

 Bot. Dep. Jam. ^%\. viii. p. 89). — This deals with "Potato-leaf Blight," or 

 " Early Blight " {Alternaria solani) ; " Potato Blight, Late Blight or 



