572 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
strate that there is no foundation for the belief that an increased crop yield, 
commensurate with expenditure incurred, may be expected from its use. 
C. P. C. 
Raspberry and Loganberry Beetle. By A. H. Lees (Ann, Rep. Agr. Res, 
Stn. t Long Ashton, 191 7). — The beetle Byturus tomentosus causes so much damage 
to raspberries and loganberries as to threaten the loganberry industry in some 
places. Three sprayings with nicotine wash were instrumental in reducing the 
amount of infection to a marked degree. The method was to spray with 2 per 
cent, paraffin emulsion and five minutes afterwards with a nicotine wash, consist- 
ing of soft soap 20 lb,, paraffin 2 gallons, nicotine £ lb., water 100 gallons. 
F. J. C. 
Rats : How to exterminate them. By R. Sharpe (Jour. Bd. Agri. vol. xxiv. 
No. 12 vol. xxv. No. 1 — A long article by a practical man which cannot be 
properly abstracted. It points out the great losses due to rats, their natural 
enemies, and various methods of poisoning, trapping, &c. Illustrations are given 
of traps in position. — G. C. G. 
Rhizoctonias Parasitic in America. By Geo. L. Peltier (U.S.A. Exp. Stn., 
Illinois , Bull. 189, pp. 283-390, June 191 6 ; 23 figs.). — Two species of truly 
parasitic Rhizoctonias are recognized in America : the common form (Rhizocionia 
Solani Kuhn), Corticium vagum B. and C, which is widely distributed and occurs 
on a large number of plants ; and Rhizocionia Crocorum (Pers.) DC, with alfalfa 
and potato as hosts. Another Rhizoctonia, Corticium ochroleucum (Noack) 
Burt, is occasionally found on leaves of apple and pear. About 165 species 
of plants are more or less subject to attacks of Rhizoctonia. 
The author thinks, as a result of inoculation experiments with numerous 
types of plants, that all the strains, obtained from a wide range of hosts of 
different geographical origin, can attack the same species of plant and produce 
the same characteristic symptoms. The virulence of R. Solani is variable, and 
it is found abundantly in cultivated soils, where it can live upon weeds or dead 
organic material. — A. B. 
Rhododendron aurieulatum. By A. D. (Irish Gard. xii., Oct. 1917. P- *49)- — 
A striking new species introduced by E. H. Wilson from China. — E. T. E. 
Rhododendron oreotrephes. By J. W. B. (Irish Gard. xiii., Jan. 191 8, 
p. 5). — A brief descriptive note on this desirable new species, discovered by 
George Forrest. Its rosy-lavender flowers make it attractive. — E. T. E. 
Rhododendron rubiginosum. Anon. (Irish Gard. xiii., Aug. 1917, p- n8; 
1 fig.). — A useful but neglected species introduced by Abbe Delavay. It should 
be much more largely grown. It flowers in April and May, colour being rosy 
lilac— E. T. E. 
Rhododendrons, Chinese. Anon. (Irish Gard. xiii., May 1918, p. 72 ; 1 
fig.). — A note on some useful Rhododendrons collected in China by George 
Forrest. — E. T. E. 
Rhododendrons, Some Notes on. By J. R. of B. (Irish Gard. xiii., June 
1918, pp. 82-86). — A delightful article by a well-known tree and shrub 
enthusiast, dealing with a large number of beautiful species and varieties. 
E. T. E. 
Rosa cerasocarpa Rolfe (Bot. Mag. t. 8688"; Dec. 1916). — A climbing species 
with many-flowered clusters of white flowers in June, each about inches across, 
and deep-red globose fruits in November. The sepals and styles are deciduous. 
Native of China. — F. /, C, 
# 
Rosa Davidii Crep. By R. A. Rolfe (Bot. Mag. t. 8679 ; Oct. 191 6) .—A hardy 
shrub 5 to 6 feet high, with leaves 3 to 4 inches long, grey-puberulous beneath, 
and rose-pink flowers about £ inch across in loose corymbs. Fruits ovoid, pink, 
with persistent sub-erect sepals. Common in mountains of Moupine, W. Szechwan, 
where the seed was collected by Mr. Wilson in 1908. — F. J. C, 
Rosa Moyesii. By R. M. P. (Irish Gard. xiii. p. 107, July 1918). — A beautiful 
plant introduced by Wilson. Flowers large, and brick- red colour. Bush habit. 
Height, 6-8 feet. Fruits dark red, bottle-shaped £ Propagation by seeds sown 
indoors. — E. T. E. 
