NOTES AND ABSTRACTS. 



363 



ment of the flowers of Diospyros virginiana, the four megaspores, the 

 development of the endosperm and embryo (polyembryony occurs), 

 and the development of the pollen, mother-cells, and tetrads. 



G. F. S. E. 



Disa lugrens (Bot. Mag. t. 8415). — South Africa. Family 

 Orchidaceae ; tribe Ophrydme. Herb, terrestrial, 1^-2 feet high. 

 Leaves 8-20 inches long; scape 1^-2 feet long; raceme laxly 5-15 

 flowered, 4-8 inches long; flowers 1^ inch long and 1 inch wide; 

 sepals posterior, pale blue with greenish stripes, falcate; lip recurved, 

 deeply multifid-lacerate, green. — G. H. 



Diseases of Cultivated Plants in Ohio, A Brief Handbook of. 



By A. D. Selby {U.S.A. Exp. Stn., Ohio. Bull. 214).— Part I. treats 

 of plant diseases in general, the relation of host and parasite, parasitic 

 fungi, and various methods by means of which the practical man can 

 identify and control disease in plants. 



A number of diseases of trees caused by the larger Basidiomycetes 

 {Polyporus, &c.), root infections, parasitic foliage, and fruit diseases, 

 bacterial and non-parasitic diseases are briefly described and figured. 



Several good standard fungicides and the methods employed im 

 mixing them are given, both for plant and seed treatment, and thd 

 author also advocates soil treatment (especially in forcing-houses), 

 either by heat, thorough steaming of the soil, or by the use of formal- 

 dehyde drench, 



2-4 liquid lb. of formalin- (40 per cent, commercial), 

 Fifty gallons of water. 



The author then goes on to treat of storage rots in fruits, potatos, 

 and onions. 



The disinfection of onions may be carried out under the Maine 

 formula for formaldehyde gas : — 



3 lb. formalin (40 per cent.), 

 23 oz. potassium permanganate, 



is sufficient for 1000 cubic feet of space occupied by crates or trays. 



A similar treatment is suggested for stored apples and pears, but 

 so far has not been applied. 



Part 11. deals with special diseases in Ohio, arranged alphabetically 

 according to the host plants.— D. M. G. 



Dombeya ealantha {Bot. Mag. t. 8424).— British Central Africa. 

 'P^milj Sterculiaceae ; trihe Dombeyeae. Shrub, 12 feet high. Leaves 

 3-5 lobed, 12 inches across; cymes corymbiform, 15 fid.; corolla IJ 

 inch across, rose-coloured. — G. H. 



Doug-las Fir, Properties and Uses of. By McGarvey Gline 

 and J. B. Knapp {U.S.A. Dep. Agr. Forest Service, Bull. 88; 

 June 1911).— An exhaustive paper on the properties and uses of the 

 timber of the Douglas Fir, which, as the tree thrives well in almost 



