NOTES AND ABSTRACTS. 
Desmodium cinerascens Franch. By J. Hutchinson {Bot. Mag. t. 8805, 
June 1919). — Native of S.-W. China, and introduced by M. Maurice de Vilmorin 
in 1896. It is quite hardy, forming a bush 3 to 4 feet high. It flowers in October, 
the inflorescence being several inches long and the flowers rosy carmine. — F. J. C. 
Disporum pullum var. brunnea C. H. Wright {Bot. Mag. t. 8807 ; June 1919). — 
Introduced from W. Hupeh by E. H. Wilson through the Arnold Arboretum, 
this plant thrives in partially shaded situations in good sandy loam. The 
brownish tubular perianth has the segments spreading at the tips and so differs 
from the type. — F. J. C. 
Dusting the Orchard. By F. H. Dudley etc. {U.S.A., Maine, Bull., vol. 19, 
No. 3, Sept. 1920). — These papers comprise the views of four authors advocating 
the use of dust instead of liquid sprays. The advantages are time and labour 
saving, better transport, and cheaper upkeep. As with liquid spraying, a 
thorough application is necessary. The opinion of all the authors is that there 
is a good future for dusting, and the opinion of many growers is favourable. 
Two formulae are given : (i) sulphur 45 per cent., tobacco 40 per cent., and 
lead arsenate 15 per cent. ; and (2) sulphur 85 per cent, and lead arsenate 15 
per cent., and the ingredients so finely ground as to "pass through a silk cloth 
of 200 meshes to i inch. — G. F. W. 
Dusting and Spraying Experiments. By W. C, Dutton {U.S.A. Exp. Sin. 
Michigan, Bull. 102, March 1920, pp. 3-50; 20 figs.). — A detailed account 
of dusting and spraying experiments carried out during 191 8-1 9. Although 
the cost of material for dusting is higher than for spraying, the application 
costs less. 
The operation may be done when the foliage is wet or dry, but cannot be 
performed satisfactorily if there is much wind. A driving spray is unsatis- 
factory, and drenching the trees should always be avoided. Dusting effectively 
controlled apple scab and biting insects, and gave as good results as when lime- 
sulphur and lead arsenate were used. 
Results are given of the effect of dusting apples, cherries, plums, peaches, 
currants, and potatos. 
Dry lime-sulphur did not control apple scab, so that it cannot be profitably 
substituted for lime-sulphur solution. Lead arsenate is thoroughly recom- 
mended on all kinds of fruit-trees, and although calcium arsenate proved 
efficacious on potatos it was unsatisfactory on fruit-trees. — G. F, W. 
Ecology of Foliar Anatomy of some Plants of a Prairie Province in Iowa. By 
A. Hayden {Amer. Jour. Bot. vol. vi. No. 2, Feb. 1919, pp. 69-85 ; 5 plates). — 
The following is a summary of the conclusions arrived at : 
The leaves of prairie plants show a xerophytic tendency, as shown by the 
specialized palisade cells, thick-walled epidermis without trichomes, and the 
presence of water-storing tissue. The upland plants have a thinner epidermis than 
those of the lowlands. Of the alluvial basin leaves studied, 50 per cent, were 
bifacial and 12^ per cent, were centric to subcentric, while of the upland plants 
33 per cent, had bifacial leaves and 50 per cent, were centric to subcentric. — A . B. 
Ecology of Subterranean Anatomy of some Plants of a Prairie Province in 
Iowa. — By A. Hayden {Amer. Jour. Bot. vol. vi. No. 3, March 1919, pp. 87-105 ; 
12 plates). — 'A study of the anatomy of the subterranean organs of prairie plants 
shows there is a tendency to the production of prominent mechanical tissue in 
plants of dry habitats and a reduction of parenchyma. In moist habitats the 
proportion of parenchyma is greater than that of the mechanical tissue. The 
vascular tissue is variable in quantity. The subterranean stem is predominant 
as an equivalent of the primary root, especially in moist lowland regions. It 
is more efficient than the root in propagation. Primary roots which show 
secondary thickening resemble stems in their concentric manner of expansion. 
The stem, however, has a pith area which serves as a reservoir for water and there- 
fore increases its efficiency for radial distribution. 
Bibliographies are appended to both papers. — A. B. 
Electricity for Heating Greenhouses. By A. Guion {Rev. Hort. vol. xcii. 
p. 64. — Where a cheap supply of electricity is available the greenhouse may be 
heated by electric radiators, but for orchids and other delicate subjects it is 
better to use the thermo-syphon system employing an electric furnace for heatinsr 
the water.— 5. E. W. 
