512 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
Root-tubsrcles and the Influence of Nitrates as Manure. By A. J. Ewart, 
D.Sc. {Jour. Dep. Agr. Vict. Dec. 1915, p. 759). — Broad beans manured with 
nitrate of soda, others with nitrate of potash compared with no manure, in 
single and double rows, the total result showed 12-5 tons an acre with 95 lb. 
sodium nitrate an acre, 13- 9 tons with 1 cwt. potassium nitrate an acre and 12' 7 
tons controls. Root- tubercles were abundant on all the plots ; there was no 
evidence of any suppression of root-tubercle formation by potassium nitrate 
or by sodium nitrate in the quantities applied. The largest root-tubercle was 
found on a plant from the control plots, but there was no generally greater 
abundance or size of the root-tubercles in the plants of the control plots as 
compared with the others. Hence, although the nitrates used did not diminish 
appreciably the formation of root-tubercles, their use as manures in the case 
in question would have been highly unprofitable, the plants being able to gain 
all the nitrogen they required through their root- tubercles and from supplies 
already present in the soil. — C. H. H. 
Roots, The Orientation of Primary Terrestrial, with Reference to the Medium 
in which they are Grown. By Richard M. Holman (Amer. Jour. Bot. vol. iii. 
No. 6, June 1916, pp. 274-318 ; 7 figs.). — The following conclusions were obtained 
from a series of experiments on the roots of Vicia-Faba L. (var. major and var. 
equina), Lupinus albus L., and Pisum sativum L., grown in various media. 
1. The difference in the behaviour relative to gravity of roots in air and 
in earth is not due to differences in the amount of water in the media. 
2. The difference in behaviour is not the result of change in the geotonus 
of the roots due to their stay in air, whether weakening or loss of geotropism 
as Sachs suggested, or assumption of plagio-geotropism as Nemec reported. 
3. That, as was shown by experiments with media, the resistance of which 
to the root's advance could be widely varied, the failure of the roots in air to 
reach the vertical is due to the absence of mechanical resistance to the advance 
of the root tip through that medium. 
4. The -secondary curvature of roots in earth, sand, sawdust, Sphagnum, 
or other such media, is complete because the resistance of these media to the 
advance of the root tip causes passive depression of the root and prevents the 
complete flattening of the tip curvature. 
5. That thigmotropism is not a factor in the difference in the behaviour 
of roots in air and in earth, or other non-fluid media. 
6. The resistance offered by the medium to movements of the root tip in- 
fluences not only the course of the secondary curvature, but also the course 
of the primary curvature ; that is, the curvature directly following the placing 
of the root in a position of stimulation. — A. B. 
Rose, American Piilar. By S. Mottet {Rev. Hort. Oct. 16, 1915). — One 
illustration of this splendid climber and describing its robust habits. — C. T. D. 
Roses, Recent Chinese. By R. A. Rolfe (Gard. Chron. July 22, 1916, p. 37). — 
Rosa Davidii, R. corymbulosa, R.setipoda, R, Sweginzowii,R. sertata, R. elegantula, 
and R. Moyesii described from observations of their habit and flowering at Kew. 
E. A. B. 
Roses, War (Le Jard. vol. xxx. p. 76 ; 3 figs.). — 'Constance' resembles 
' Rayon d'Or,' but is much superior. It is hardy and vigorous, with long orange- 
yellow buds, streaked with crimson. The large flowers are cadmium-yellow 
when they open, and change to golden-yellow. ' Admiral Ward,' a hybrid tea 
of vigorous and erect habit, is very floriferous. The buds are dark red, and the 
velvety flowers are crimson, shaded with bright red and purple. 
' Gloire des Beiges,' a seedling from ' Mme. Abel Chatenay,' is valuable for cut 
flowers, as the long stems bear a number of buds which open in water. The buds 
are crimson in colour. The flowers are large and double. — 5. E. W. 
Salpiglossis, Gloxinia-flowered. By S. Mottet (Rev. Hort. Dec. 16, 1915)- — 
Coloured plate showing six varieties, very handsome. — C. T. D. 
Saxegothaea conspieua (Bot. Mag. t. 8664). — Chile. Nat. Ord. Taxaceae. 
Tree, 30-40 feet high, or a shrub. Leaves persisting for 4-5 years, linear, | inch 
long. Female cones subglobose. Fruit fleshy. — G. H. 
Sclerotinia sp. on Ginseng. By J. Rosenbaum (Jour. Agr. Res. v. p. 291, 
Nov. 1915). — Two rots of the valuable medicinal plant ginseng have been de- 
scribed, a white rot and a black. The former is proved to be due to the Sclerotinia 
