NOTES AND ABSTRACTS. 
103 
another when grown in close proximity is a very complex phenomenon. When 
the food supply is limited the chief factor of competition is that of food, in par- 
ticular the amount of nitrogen available. Even when ample supplies of food 
and water are available for individual plants, the decrease in light caused by 
overcrowding is a most potent factor in competition. — R. C. S. R. 
Potatos, Grades for. By Hartley E. Truax {U.S.A. Dep. Agr., Circ. 96, 
May 1920). — In order to reduce waste and conserve transport facilities during 
the war, the Food Administration issued a rule, requiring the use of the 
United States grades by licensed dealers. The regulation was cancelled in 
1 91 8, but the use of grades has been continued voluntarily. — V. G. J. 
Potatos, Protection of, from Cold in Transit: Lining and Loading Cars. 
(U.S.A. Dep. Agr., Bull. 1091, Feb. 1920; 22 figs.). During the winter of 
1917-18, 75 per cent, of cars were either lined or loaded incorrectly. This 
bulletin explains successful methods. — V. G. J. 
Rhododendron Sargentianum Rehder and Wilson. By J. Hutchinson (Bot. 
Mag. t. 8871 ; December 1920). — A dwarf species collected by E. H. Wilson in 
W. Szechwan. Probably best in half shade, hardy, bearing smallish pale-yellow 
flowers in terminal clusters in May ; leaves about \ inch long, finally smooth 
and polished above, softly scaly below. — F. J. C. 
Rhododendron strigillosum Franch. By J. Hutchinson (Bot. Mag. t. 8864 ; 
December 1920). — Seed of this Szechwan species was collected by E. H. Wilson 
for Messrs. Veitch, and it has flowered at Kew in early spring. The flowers are 
red, crimson, or white, and the nectaries black ; the leaves narrowly oblong- 
lanceolate, 3 to 6 inches long, with crisped hairs beneath. The young shoots 
are very bristly. — F. J. C. 
Seed, Physiological Predetermination : The Influence of the Physiological 
Condition of the Seed upon the Course of Subsequent Growth and upon the Yield. 
By Franklin Kidd, M.A., D.Sc, and Cyril West, A.R.C.Sc, D.Sc, F.L.S. (Ann. 
Appl. Biol. vol. vi. No. 1, Sept. 1919 — continued from vol. v. pp. 1-26; plate 
and diagrams). — The effect of conditions during germination and in the early 
seedling stage upon subsequent growth and final yield. Physical treatment of 
seed includes high and low temperatures, electrical discharge and X-rays ; 
chemical treatment with acids and chemical agents other than acids. In 
conclusion the evidence seems to show that the factors which influence the plant 
during its earliest stages of development have a more or less pronounced effect 
upon the whole of its subsequent life-history. A bibliography is appended. 
R. C. S. R. 
Street Trees. By F. L. Mulford (U.S.A. Dep. Agr., Bull. 816, June 1920; 
37 figs.). — Deals with the planting and after-care of shade trees in streets and 
towns.— V. G. J. 
Syringa reflexa C. K. Schneider. By S. A. Skan (Bot. Mag. t. 8869 ; 
December 1920). — A shrub up to 13 feet from Hupeh, introduced through E. H. 
Wilson. Distinct by its pendulous inflorescence and warted fruits. Hardy 
in England. Flowers purplish-red without, whitish inside. — F. J. C. 
Tomato Moth, The Habits of the Glasshouse, Hadena oleracea, and its Control. 
By LI. Lloyd (Ann. App. Biol. vol. vii. No. 1, Sept. 1920, pp. 66-102; 
4 diagrams, 6 tables, 6 figs., 3 plates). — This paper deals with the life-history of 
the tomato moth, which is spreading in the Lea Valley. A list of food plants is 
given. The methods of control are very fully dealt with. 
Spraying, larva- and moth-trapping, and the destruction of pupa? are advised. 
Fruit as well as foliage is eaten, as the latter alone is insufficient for the 
caterpillar. Spraying with lead arsenate should be done at least three times : 
(1) Seedlings in pots, (2) just after planting out, and (3) about a month before 
picking fruit, and this last operation is the most important. 
Constant baiting for moths should be done throughout the growing season 
by jars baited with ale, treacle, and i-per-cent. sodium fluoride. 
Larvae may be trapped in sacks placed about the houses, and collected 
every third week and dipped in boiling water. — G. F. W. 
Tomato, Stripe Disease of. Studies In Bacteriosis, IV. By Sidney G. Paine 
(Ann. Appl. Biol. vol. vi. Nos. 2 and 3, Dec. 1919, pp. 183-202; plates and text 
figs.). — A stripe disease of tomatos growing under glass is described, the causal 
organism a small yellow bacillus, believed to be identical with Bacillus lathyri. 
