March, 1920] GENETICS 87 



Euonymus japonicus lati 'foil us var. varicgata, and for three varieties of Pelargonium. The 

 white-skinned and green-skinned varieties of Coproxmu Haueri are described. The various 

 sports are illustrated by 16 excellent figures in color, and one text figure shows the distribu- 

 tion of chlorophyll-and non-chlorophyll-bcaring cells in Euonymus. Reversals in periclinal 

 chimaeras are considered to be rare and due to some instability in the growing point, such as 

 a greater vigor of the green core, or to injury. 



Author suggests that the phenomena of reversal in variegated periclinal chimaeras may be 

 duplicated in respect to somatic and genetic distinctions in characters not thus visible, thereby 

 bringing about changes in the properties of the layer from which germ cells arise. — A. B. 

 Stout. 



595. Bateson, W., and Ida Sutton. Double flowers and sex linkage in Begonia. Jour. 

 Genetics 8: 199-207. PI. 8. June, 1919.— See Bot. Absts. 3, Entry 978. 



596. Beauverie, J. Les methodes de selection appliquees aux cereales de semences. 

 Etat actuel de la question. [Methods of selection applied to seed grains. Present status of the 

 matter.] Rev. Gen. Sci. Pur. et Appl. 30:79-87, 108-114. 1919.— Summarizing the work of 

 Biffen, Nilsson, and others, author points out that the method of selecting the best seeds, 

 year after year, of a mixture of strains seldom leads to the establishment of a superior variety 

 with any degree of permanence, the quality of the seeds produced varying from year to year 

 according to weather, cultural, and other conditions, with an undue proportion of inferior 

 seeds in each crop. On the other hand, selecting from the progeny of a single individual, that 

 is, in a "pure line" or in "pedigreed" stock, one has the chance of finding strains which will 

 be permanently superior, year after year. In these strains some characters are fixed, such as 

 the shape, color, and roughness of the grains; some vary with the conditions, such as length 

 of stems, and weight of grains, though being more or less controlled by heredity; while still 

 others vary entirely with the conditions of culture. But in the pure line the behavior of the 

 individual as influenced by circumstances is not necessarily repeated in its own descendants, 

 the behavior of the latter being controlled by its ancestors. There are doubtless many 

 "pure lines" in nature, not recognized or recognizable. Occasionally one of these may "sport" 

 or mutate, in a striking and desired manner, or a striking and desired change may come about 

 by accidental crossing. Man takes advantage of the possibility of crossing, and by deliberate 

 hybridizing may secure a new and desired combination of characters already existing, such as 

 superior fecundity with disease resistance, resistance to cold, etc. The paper also includes 

 an historical sketch of the development of plant breeding through pedigree cultures at seed- 

 control stations in various countries of the world, recognition of the leaders, and a statement 

 of some of their main results. — G. J. Peirce. 



597. Bensaude, Mathilde. Recherches sur le cycle evolutif et la sexualite chez les 

 Basidiomycetes. [Researches on the evolutive cycle and sexuality in the Basidiomycetes.] 156 

 p., pi. IS, fig. 30. [Dissertation.] Nemours, 1918. — "Miss Bensaude has investigated Cop- 

 rinusfimentarius, Armillaria mucida, and Tricholoma nudum. The work includes two phases: 

 (1) the morphology and cytology of the mycelia, and (2) the results obtained from the study 

 of the single spore cultures of C. fimentarius. — The mycelia of the 3 species were obtained from 

 germinating spores as well as from material collected in the field. The author accepts Falck's 

 classification of the mycelia into primary, secondary, and tertiary forms. The claim is made 

 that the first few days after the germination of the spores the resulting mycelia belong to the 

 primary class, in which the hyphae are partioned off into cells which contain from one to many 

 nuclei. These uninucleate cells may give rise to varying numbers of uninucleate oidia. 

 Disarticulated hyphal cells, which she calls "pseudoidia," are also formed which, like true 

 oidia, may germinate. The nuclei in the germ tubes divide amitotically. Cross-w r alls with 

 clamp connections never appear in the hyphae of the primary mycelia. Miss Bensaude grew 

 single spores of C. fimentarius in pure cultures, and succeeded in isolating 10 single spores. 

 Of these, 4 germinated, and in 2 cultures primary mycelia were obtained which did not produce 

 carpophores. When parts of each mycelium were mixed in a culture, a secondary mycelium 



