FIELD CROPS, 225 



Mutation in Penicillium glaucum and Aspergillus niger, H. J. Waterman 

 {Ztschr. Gdrungsphysiol., 3 (1913), No. 1, pp. I-I4, fig. 1). — Coucludiug a dis- 

 cussion of the causes of mutation and the metabolism of these mutants, the 

 author states that mutation is related in both cases to the same factors limiting 

 development, these including poisons, narcotics, etc., as listed. 



A possible mutant in the bellwort (Oakesia sessilifolia) which, prevents 

 seed formation, A. F. Blakeslee and A. F. Schulze {Science, n. ser., 39 (1914), 

 No. lOOS, pp. 621, 622, fi,gs. 2). — The authors describe a form of the sessile- 

 leaved bellwort iu which the pistil is shorter and thicker than in normal 

 flowers and the three stigmas are transformetl into functional stamens, each with 

 a pair of pollen sacs. The stigmatic anthers are said to be well formed and 

 filled with perfect pollen, and on account of the transformation it seems that 

 the possibility of fertilization is completely prevented. 



A study of semisterility, J. Belling (Jour. Heredity, 5 (1914), ^0. 2, pp. 

 65-73, figs. 7). — The results of a study of hybrids of several species of Stizolo- 

 l>ium are given, from which the author concludes that accui-ate knowledge of 

 the degree of sterility of .some hybrid plants may be obtained by microscopic 

 examination of the pollen of healthy flowers and sections of the ovules. The 

 explanation of the random abortion of half the pollen grains and half the 

 embryo sacs is apparently due to the segregation of Mendelian factors and not 

 to the action of these factors on the zygotes. Semisterility resulting from 

 crossing is apparently one of the simplest cases of sterility, and a knowledge 

 of its inheritance, it is believed, will help iu the investigation of more com- 

 plicated problems of sterility found in many first-generation hybrids. 



Partial barrenness in Liibeck currants, E. Zacharias (Jahrb. Hamburg. 

 Wiss. Amt., 29 (1911), Bciheft 3, pp. 129-11,9). — This work was carried forward, 

 after the author's death in 1911, by W. Himmelbaur, testing the capability, as 

 regards pollination, of several varieties of Rihes pallidum. Detailed results are 

 given. It is stated that good results were obtained as regards fertility of the 

 resulting forms by crossing Liibeck with Afsmiter. The normally low fertility 

 of the latter is ascribed to faulty pollen. 



Notes on the life history of Ribes pallidum, W. Himmelbaue (Jahrb. Ham- 

 burg. Wiss. Anst.. 29 (1911), Beiheft 3, pp. 151-245, figs. 6.9).— Reporting fur- 

 ther studies with R. palHdum, carried out iu considerable cytological detail at 

 different stages in its early life history in relation to the fertility of this form 

 (considered to be a hybrid of R. petrwum and R. rubrum). which while only 20 

 to 40 per cent is still higher than that of either parent, the author states that 

 R. pallidum is probably identical with Liibeck currant. Individuals of the latter 

 variety are said to show sudden sterility associated with other alterations of 

 habit which are mentioned. 



This work concludes with a bibliography. 



FIELD CROPS. 



Farm crop surveys, E. G. Montgomeey (Jour. Amer. Soc. Agron., 5 (WIS), 

 No. 4, pp. 232, 233). — This paper relates to methods and gives some results of a 

 potato survey in which about 700 records were taken in a county in New York. 

 It is noted that " certain problems came to be outstanding as the inquiry pro- 

 gressed. It now appears that if experimental work has been undertaken pre- 

 vious to the survey we should not have hit on the principal problems in all 

 cases. Also some grower, somewhere, has worked out in practice an answer 

 to many problems, making investigation unnecessary. I am convinced that it 

 would be very profitable, before an extensive line of investigation is undertaken 

 with a crop, to first make a survey of this crop." 



