NOTES AND ABSTKACTS. 



567 



a. 5 per cent, solution stripped the trees of leaves ; and though the effect of 

 spraying with sea water (2*7 per cent, salt) was as bad, though slower, in 

 its action it is considered probable that the greater part of the damage 

 done to vegetation near the sea is due to wind and not to salt, many plants 

 which flourish near the sea being quite unaffected by spraying with sea 

 water. The bad effect of brine on foliage, as on insect eggs, is held to be 

 due to the osmotic action of the salt. In dealing with the effects of 

 washes generally (pp. 103-107) it is pointed out that repeated treatment 

 with a strong wash may produce injury even when a single dressing 

 appears to be without effect, and that other varieties of apples may be 

 more susceptible to injury than those upon which the experiments were 

 conducted. Though the authors believe that even a 2 per cent, strength 

 of paraffin emulsion may generally be used with safety, yet a 1 per cent, 

 wash caused some scorching when applied at the time the blossom buds 

 were opening. No injury to trees in the dormant state has yet been 

 noticed from the application of emulsions containing as much as 36 per 

 cent, of paraffin (p. 126). A 50 per cent, emulsion and undiluted paraffin 

 were used on apple trees in leaf, and both perfectly destroyed woolly aphis 

 (p. 109) as far as it can be destroyed by treating the branches alone and 

 without lasting injury to the trees, the paraffin causing less injury than 

 the 50 per cent, emulsion. Later experiments in this dangerous practice 

 are detailed in the " Tenth Eeport " (pp. 13-21), dealt with in the July 1909 

 "Journal." The nature of the action of insecticides is discussed (pp. 

 110-113) with reference to the part played by osmosis, and also to the 

 enhancement of the effect produced by two insecticides acting together as 

 compared with the action of either separately, as, for instance, paraffin 

 and caustic soda. — A. P. 



Staehys grandiflora. By K. Fischer (Die Gart. p. 447, Sept 18, 

 1909). — Notes on this useful, hardy perennial. The plant grows about 

 2 feet in height. The leaves are cordate and hirsute, and the flowers are 

 violet red, lasting a considerable time. The time of flowering is 

 during the summer months. — G. B. 



Strophantus Preussii. By O. Stapf (Bot. Mag. tab. 8250).— Nat. 

 ord. Apocynaceae. West Africa. A climbing or straggling shrub ; stems 

 to 12 feet long ; leaves 2-4 inches long and H-2 inches wide ; cymes 

 terminal in many-flowered corymbs ; corolla 1 inch across, yellowish- 

 white, the tube reddish, the tips ending in filiform tails, to 1 foot in 

 length.— G. Hy 



Sulphate of Iron and Apple Scab. By L. Bey (Pom. Franc, 

 June 1909, pp. .167-1 70).— In an article on copper salts and cryptogams 

 the author concludes by recommending the use of sulphate of iron as a 

 winter spray for apple trees, the boughs of which are infected with apple- 

 scab fungus. — C. H. H. 



Sweet PotatOS. By A. Bodely (Le Jard., vol. xxiii. No. 534, p. 155 ; 

 May 20, 1909 ; 2 figs.).— The tubers of Convolvulus Batatas are much 

 recommended as a substitute for potatos. They are propagated in March, 

 either by cutting up the tuber, and planting the bits containing an eye, 



