250 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
and Agropyron sp., which form the two most valuable pasture grasses of the 
district, is recorded. — F. J. C. 
Weeds of New South Wales (continued). By J. H. Maiden (Agr. Gaz. N.S.W. 
vol. xxvii. pp. 865-867; vol. xxviii. pp. 46-48, 131-133, 181-184, 244-246; 
8 col. plates). — Coloured plates represent the Poison Buttercup (Ranunculus 
sceleratus), the Rough-seeded Buttercup (R. muricatus), the Sow Thistle (Sonchus 
oleraceus), Cat's Ear (Hypochaeris radicata), Petty Spurge (Euphorbia Peplus); 
Bushy Star wort (Aster subulatus), St. Barnaby's Thistle (Centaurea solstitialis) ; 
Groundsel (Senecio vulgaris), Prickly Lettuce (Lactuca scanola), and Solivasessilis. 
R. sceleratus should be dug up and destroyed on account of its poisonous pro- 
perties.— 5. E. W. 
Western Plant Studies, IV. By A. Nelson and J. F. Macbride (Bot. Gaz. 
vol. lxii. No. 2, Aug. 191 6). — The authors give detailed botanical descriptions 
of the following species : — Plagiobothrys Harknessii, n. comb. ; P. folioceus, n. 
comb. ; Cryptantha vincteus, n. sp. ; Oreocarya dura, n. sp. ; O. propria, n. sp. ; 
Amsinckia carinata, n. sp. ; Mertensia Palmeri, n. sp. ; Pentstemon minidokanus, 
n. sp. ; P. payetensis, n. sp. ; Machaer anther a rhizomata, n. sp. ; M. inops, 
n. sp. ; Macronema filiformis, n. sp. ; M. glomerata, n. sp. ; M. Walpoliana, 
n. sp. ; M. scoparia, n. sp. ; M. pulvisculifera, n. sp. ; M. imbricata, n. sp. ; 
Evax breviflora, n. comb. ; Lactuca spicata var. multifida, n. comb. — R. J. L. 
Wetting Substances, Accessory, with Special Reference to Paraffin Emulsions. 
By A. H. Lees, M.A. (Ann. Appl. Biol. iii. No. 4, April 1917, pp. 141-149 ; 
tab.). — One of the most important points of a spraying fluid for insect or fungus 
pests is its wetting power. The addition of soft soap to certain proprietary 
insecticides increases their wetting powers and therefore their killing powers. 
Soap is ineffective against colonies of woolly aphis on account of the waxy 
thread coverings excreted by the insects, and the same trouble is experienced in 
the case of American Gooseberry Mildew. 
Experiments with paraffin emulsions as " wetting agents " were very fully 
carried out. The cheapest and most effective mixture is a 2 per cent, emulsion 
(20 lb. soap to 100 gals, water, and 2 gals, paraffin to 100 gals, water). Its 
value lies not so much in its own killing powers but in its action as a carrier 
for other fungicidal or insecticidal bodies, which, alone, would not effectively 
eradicate the pest. Thus, liver of sulphur used with the 2 per cent, mixture 
has given promising results on a commercial scale against American Mildew. 
It has also been found possible to kill the raspberry beetle with the 20 per cent, 
mixture united with a dilute nicotine solution. — R. C. S. R. 
Weymouth Pine in the Surrey Desert. By B. W. Adkin (Quart. Jour, of 
Forestry, x. pp. 185-193 ; July 1916). — The Weymouth pine is no recent 
introduction. It has been planted somewhat extensively in this country for 
about two hundred years. It ranks highly both for ornament and sylviculture. 
In its native land the Weymouth pine is said to have attained a height of from 
150 to 175 feet, and a girth of 10 to 15 feet ; but in Britain a height of 60 to 80 feet 
may be taken as an average; trees overgo feet are rare, and the tallest ever recorded 
was but 122 feet high. 
On suitable soils and situations Weymouth pine should give a better financial 
return than Scots pine, for three reasons : firstly, it should yield a larger number 
of cubic feet an acre on account of its more rapid growth and its greater shade- 
bearing properties ; secondly, it should be ready to cut on a shorter rotation, 
and thus prevent such an accumulation of compound interest ; and, thirdly, if a 
good market could be found for British timber, Weymouth pine should fetch a 
considerably higher price a cubic foot than Scots pine. 
From all points of view, therefore, it would appear that Weymouth pine is 
to be regarded as a good tree to grow for sylvicuitural purposes in Britain. 
A. D. W. 
Willows : their Growth, Use, and Importance. By Geoi-ge N. Lamb [U.S.A. 
Dep. Agr., Bull. 316, Dec. 20, IQ15). — There are in the United States and Canada 
from eighty to a hundred species of willows, distributed from the Gulf of Mexico 
to the Arctic Circle, and from tide-water to the tops of the highest mountains. 
They range from a tiny plant a few inches high to a forest tree 4 feet in diameter 
and 140 feet in height. All the shrubbery species are useful as soil cover, forage, 
or basket material. Scarcely more than a dozen, however, are of prime economic 
