362 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Dendrobium Dearei. By E. Hiethe (Orchis, vol. vi., pt. ii., 



p. 23 ; 1 plate). — This Dendrobium requires plenty of moisture in a 

 warm house, with shade in summer. — S. E. W . 



Dendrobium Wardianum gig-anteum. By A. Heydt {Orchis, 

 vol. vi. pt. iii. p. 56). — This beautiful orchid bears fragrant cream- 

 coloured flowers from February to April. It requires a moist atmosphere 

 and a temperature of 68^ F.— .S'. E. W, 



Dichapetalum venenatum (Eng. and Gilg.), A Plant Poisonous 

 to Cattle in German South-West Africa, with some Remarks 

 on other Poisonous Dichapetalum. By A. Engler {Nat. Konig. 

 Bot. Berlin, vol. v. No. 48, pp. 244-251; Dec. 1911; 2 figs.).— The 



appearance and distribution of Dichapetalum venenatum is described. 

 Its young leaves are readily eaten by oxen, which quickly succumb to 

 its effects. A very few leaves are sufficient to kill an ox. The fruit, 

 which is about the size and colour of a Mirabelle, is not unpleasant 

 to the taste, but is poisonous. Seven other poisonous species of African 

 Dichapetalum are described. — R. B. 



Dimerosporium. By F. Theissen, S.J. {Beih. Bot. Cent. 

 Bd. 29, Abt. ii. Heft 1, pp. 45-73). — This is a critical revision, with 

 localities and bibliography of all the species of this genus. — G. F. S. E. 



Dimorphic Leaves of Cotton and Allied Plants in Relation 

 to Heredity. By 0. F. Cook {U.S.A. Dep. Agr., Bur. PL Ind., 



Bull. 221; 1912). — A study of the abrupt changes presented by leaves 

 of cotton and allied plants which the author considers analogous to 

 mutative variations. A distinction is drawn between the expression 

 and transmission of plant characters as it is obvious that widely differ- 

 ing leaf variations presented on an individual plant are not to be 

 explained by the theory of alternative inheritance. We quote the 

 author : * ' Dimorphism and Mendelism may both be interpreted as 

 phenomena of alternative expression. . . . The facts of heredity and 

 breeding can be better understood if transmission be considered as 

 including the whole ancestral series of characters. Transmission 

 inheritance is a comprehensive process, while expression inheritance is 

 partial and alternative, different characters being expressed in different 

 individuals or in different stages of individual development." We think 

 this quotation will suffice to induce students of heredity to study this 

 bulletin, which is of considerable importance. — E. A. Bd. 



Dioscorea, Sweet Potato. By E. de Noter {Le Jard. xxv. 592, 

 p. 312, Oct. 20, 1911; 5 figs.). — This article enumerates the various 

 species of Dioscorea, and advocates their use as a winter vegetable, 

 some thirty kinds being now available. Another note on the subject of 

 their cultivation will be found on p. 359, No. 595, of Le Jar din. 



F. A. W. 



Diospyros, Morphologry of. By Stella M. Hague {Bot. Gaz. 

 pp. 34-44, July 1911; 3 plates). — The author describes the develop- 



