l6a JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY, 



Soil Reaction indicated by the Hydrogen Electrode. By J. K. Flummer 

 {Jour. Agr. Res. xii. Jan. 1918, pp. 18-31). — The hydrogen electrode has been 

 used for indicating soil reactions in wide areas of South-East United States, and 

 has shown effects ranging from " true neutrality " to excessive " true acidity " 

 in these soils. 



The effects of certain fertilizers on the H ion concentration of long-treated soils 

 have shown (1) that ammonium sulphate has materially increased the H ion 

 concentrations. This acidity has developed often to the subsoil. (2) Sodium 

 nitrate has slightly reduced the acidity oi the plots to which it has been applied. 

 (3) Potassium sulphate increases the " acidity " when applied to soils, but 

 not to the same extent as ammonium sulphate. (4) Acid phosphate does not 

 appear to have affected in either direction the H ion concentrations of field plots. 

 (5) Lime materially increases the OH ion concentrations in field plots when added. 

 The acidity developed from ammonium sulphate is more intense in the film than 

 in the free water of the three soils. Monocalcic phosphate does not change 

 in anyway the soil-film water until excessive amounts are added. — A. B. 



Soil Solutions, Biological Activities and Concentration of. By C. E. Miller 

 Jour. Agr. Res. vol. xiii. No. 4 ; April 1918, pp. 213-223). — The effects of 

 various salts on ammonification are greatly modified by the nature of the soil. 

 For the four salts studied (MgSG 4 ; CaN0 3 ; CaCl 2 ; KC1), each gave a definite 

 point where the ammonification of dried blood in sandy loam was depressed, 

 while only one salt gave such a point with clay loam. The cause of these vari- 

 ations has yet to be investigated, but it is possible that chemical reaction 

 between the salt added and the soil constituents may play some part. The 

 amount of dried blood had an appreciable effect upon the osmotic pressure of 

 the soil solution, the increase depending upon the class of soil. The effects of 

 various salts in soils offer much opportunity for thorough investigation, and 

 will be found to depend largely upon improved methods. — A. B % 



Spinach Mildew (Zur Entwickelungsgeschichte des Spinatschimmels (Perono- 

 spora Spinaciae [Grev.] Laub.). By J. Eriksson (Arkiv for Botunik, Stocnholm, 

 xv., No. 15 ; pp. 1-25 ; pLtes). — The author describes and figures the well- 

 kn^wn false mildew of the spinach and announces the discovery of "mycoplasm " 

 in the diseased plants similar to tnat which the same author has described in the 

 case of wneat rust, hollyhock rust, and some other diseases (see e.g., Jour, 

 (R.H.S. xxxiv. p. 469, 1908-9), — F. /, C, 



Stauropsis Imthurnii Rolfe. (Bot. Mag. t. 8714 5 June 191 7.) — A native 



of the Solomon Islands. A plant for the tropical orchid house. Inflorescence 

 a loose panicle, flowers medium-sized, white with violet-blue markings on the 

 hp. — L, C. £, 



Strawberry Leai Beetle, Notes on. By H, C. Efflatoun, F.E.S., M.R.A.C. 

 (Ann. Appl. Biol. vol. iv. No. 4, March 1918 ; pp. 206-210 ; plates). — Describes 

 the larva, pupa, and imago. The larva and imago damage the leaves in the 

 same way ; they eat the lower or upper epidermis and the soft underlying 

 tissue, leaving the opposite epidermis intact. Feeding takes place at night 

 and in early morning. Injury has been reported from Hants, Bucks, and 

 from Russia. — R. C. S, R< 



Sulphur, Effect of, on Different Crops and Soils. By O. M. Shedd (Jour. 

 Agr. Res. xi. pp. 91-104, Oct. 1917). — The result of the application of 100 lb. 

 or 200 lb. sulphur to the acre varied with different crops and soils, but the increase 

 in crop was in no case large, while in some instances there was a reduction, 



F. J. C, 



Sunflower Insects, Some (Jour. Econ. Entom. vol, x. Dec. 191 7, p. 561). — 

 It is reported under this note that Mrs. Cockerell observed bagged sunflower 

 heads to be selt-sterile : the ovaries shrink and show no development. In one 

 such head eleven ovaries contained weevil larvae (Desmoris), and in spite of lack 

 of fertilization were larger and swollen, in fact more so than normal seeds. If 

 the observation is correct we are reminded of the experiments of Loeb, in which 

 unfertilized eggs were caused to develop by various stimuli. — G. W \ G. 



Syringa Wilsonii Schneider. By W. J. Bean (Bot. Mag. t. 8739 ; December 

 1917).— Native of Western China. A handsome Lilac flowering about the 

 beginning of June and easily propagated by cuttings or seeds. Flowers pale 

 lilac, darker at the base of corolla tube, — L. C, E t 



