468 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY 



Columnea glabra (Bot. Mag. tab. 8453).— Costa Rica. Nat. 

 Ord. Gesneriaceae, tribe Cyrtandreae. Shrub, to 2 feet high, branch- 

 ing above. Leaves clustered towards the ends of the twigs, 

 inch long Flowers solitary in the upper axils ; corolla, 3 inches 

 long, scarlet. — G. H. 



Copper Sulphate, Sale of Impure (Jour. Bd. Agr. vol. xx., 

 No. 2, pp. 133-134). — A note on the adulteration of copper sulphate 

 with iron sulphate. The presence of the latter substance in copper 

 sulphate may be readily determined by dissolving a small quantity 

 in water and adding ammonia, the solution being constantly stirred 

 until a deep blue liquid is formed. Any quantity of brown flecks 

 floating in this blue liquid indicates the presence of so much iron that 

 the copper sulphate should be subjected to a proper analysis before 

 use. The desirability of obtaining a guarantee of 98 per cent, purity 

 from the seller is pointed out. — A. S. 



Cornus controversa (Bot. Mag. tab. 8464). — Himalaya and 

 E. Asia. Family Comaceae, tribe Corneae. Tree, 30-40 feet high. 

 Leaves ovate-elliptic, 3-6 inches long. Inflorescence corymbose, 

 7 inches wide. Flowers white. — G. H. 



Cotton, Egyptian, The Branching Habits of. By Argyle M'Lachlan 

 (U.S.A. Dep. Agr., Bur. PL Ind., Bull. 249 ; Sept. 20, 1912 ; plates). — 

 That the cotton plant produces two distinct types of branches which 

 are variously developed in the different varieties and types of cotton 

 and under different conditions of growth has been known for several 

 years. The excessively large size of the vegetative branches on 

 Egyptian cotton plants grown under irrigation in the Colorado River 

 Valley in Arizona and California occasions difficulties in cultivation and 

 harvesting, and causes the development of normal fruiting branches 

 to be postponed. This paper gives the results of a study of the subject 

 undertaken with the view of establishing the possibility of cultural 

 control of the production and development of either vegetative or 

 fruiting branches. The matter is still in the experimental stage, 

 but a method of recording branching habits of cotton by means 

 of diagrams has been devised. The diagrams show the position of 

 branches, the development of fruiting branches and the stature of 

 plants, and promise to be of value as records in the cultural and 

 breeding study of cotton. — M. L. H. 



Couch Grass, Poisonous. By J. H. Maiden (Agr. Gaz. N.S.W., 

 vol. xxiii. pp. 295-296 ; 1 plate). — Blue couch grass (Cyanodon 

 incompletus) sometimes contains hydrocyanic acid and is poisonous. 

 Its culms have two or three nodes ; the ligule is membranous and the 

 rachilla not produced. The non-poisonous couch grass (C. Dactylon) 

 has many noded culms, with the leaves crowded at the base ; ligule 

 a ciliate rim ; rachilla produced. — S. E. W. 



