298 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



the various types of fruits after proper selection, so that the production 

 of sweet and dry types of ciders and perries may be a matter of less 

 dependence upon chance than at present. — F. J. C. 



Cistus. By J. Pagnet (Le Jard. xxiii. 526, p. 20 ; January 20, 1909 ; 

 1 fig.). — The southern species of Cistus are more hardy than is supposed, 

 as they will usually stand 12-13 degrees of frost. Such are Cistus 

 albidus L., G. monspeliensis L., G. salvifolius L., G. ladaniferus L., 

 C. laurifolius L., G. creticus L., G. populifolius L, All these can be 

 grown from seed or cuttings, and are easily protected in winter by 

 removing to a cool house. They are charming plants for room decoration, 

 though requiring to be changed frequently. — F. A. W. 



Clearing: Log^ed-ofF Land for Farming- in the Pacific North- 

 west, The Cost Of.— By Harry Thompson (U.S.A. Dept. Agr., Bur. 

 PI. Ind., Circ. 25 ; April 1909). — The clearing of land for agricultural 

 purposes goes on swiftly in the Pacific North-West, not only the removal 

 of the timber but the clearing of undergrowth and removal of stumps 

 and roots requiring serious attention before grain or other crops can be 

 successfully cultivated. How this is done and the cost of doing it is 

 clearly stated in a series of carefully compiled tables. — A. D. W. 



Coccideae, The National Collection of. By C. L. Marlatt (U.S.A. 



Dep. Agr., Bur. Entom., Tech. Bull. 16, pt. 1). — Contains a description of 

 the collection of scale insects in the museum of the Department and notes 

 upon the methods adopted for preserving the insects and of describing 

 them.— F. J. C. 



Codlin Moth, Spraying 1 for. By M. V. Slingerland (Jour. Econ. 

 Entom. i. (1908) 6, p. 352).— This article shows that the filling of the 

 calyx cup of the apple with arsenical wash recently advocated (see Jour. 

 R.H.S. xxxiv. (1909) p. 575) is needless. All that is necessary is to use 

 a fine mist-like spray which will leave a small amount of deposit within 

 the cup. In vol. 2. p. 67, Mr. Melander returns to the subject and gives 

 reasons why great force should be used in applying the arsenical washes. 



F. J. G. 



Copper Carbonates and the Cupri-Cartaonates. By Spencer U. 



Pickering, F.R.S. (Jour. Chem. Soc, vol. xcv. ; August 1909 ; pp. 1409- 

 1429 ; table). — An investigation into the constitution of the carbonates of 

 copper and allied compounds. 



The author prefaces his paper with a useful compilation of the known 

 facts as to the compounds of copper and carbonic acid known or 

 believed to be produced under various conditions. This paper is of 

 especial interest to horticulturists in view of the important part copper 

 salts play as fungicides. 



The author found precipitation of copper sulphate in the cold 

 with normal sodium carbonate to produce invariably a basic carbonate 

 10CuO4CO. 2 . This salt is therefore largely the basis of a preparation fre- 

 quently recommended and used for potato -spraying. The salt decomposes 

 on boiling, evolving C0 2 , until finally only traces of carbonate remain. 



