NOTES AND ABSTRACTSj 



335 



Narcissus Fly, Eumerus strigatus Fin., are both fully described. 

 Their life-histories and habits are dealt with, and methods of treat- 

 ment are suggested. — A. S. 



New Plants from Western America. By Aven Nelson and T. 

 Francis Macbride {Bot. Gaz. Dec. 1913, pp. 469-479). — New 

 species of Allium, Calochorfus, Arabis, Lepidium, Chaenactis, 

 Tonestus, and Balsamorrhiza (two spp.) are described. — G. F. S. E. 



Nitrates in Soils, Some relations of certain higher plants to the 



Formation of. By T. Lyttleton Lyon and James A. Bizzell (U.S.A. 

 Exp. Sin., Cornell, Memoir I., July 1913, pp. 1-112 ; 27 figs.). — This 

 memoir, after reviewing previous work on this subject, describes 

 a series of important experiments with various grasses and cereals, 

 potatos, and soy beans on specially prepared plots. The following 

 is a summary of these results : 



The nitrate content of soil under timothy, maize, oats, potatos, 

 millet, and soy beans was different for each crop, when on the same 

 soil. There is a characteristic relationship between the crop and 

 the nitrate content at different stages of growth. During the active 

 growing period of the maize crop, nitrates were often higher under 

 maize than in cultivated soil bearing no crop. 



Under both maize and oats the nitrate content was higher during the 

 period when the crop was making its greatest draft on the soil nitrogen 

 than in the later stages of growth, in spite of the fact that the nitrates 

 in the uncropped soil were increasing, while those in the cropped soil 

 were disappearing. Changes in the moisture content or the tempera- 

 ture of the soil, after early summer, had no important effect on the 

 nitrate content of the soil under plants. 



Soil bearing alfalfa (lucerne) nitrified more rapidly than soil bearing 

 timothy. 



It is probable that the character of the organic matter left in 

 the soil by the plants determines, to some extent, the rate of nitrate 

 formation in this soil. 



Maize was the only crop following which the nitrates were higher 

 than in unplanted soil. Potato soil was the next highest in nitrates, 

 and oat soil contained least nitrates. — A. B. 



Nitrogen Fixation. By I. G. McBeth {U.S.A. Dep. Agr., 

 Bull. 131, 1913, pp. 27-33). — ^The nitrogen -fixing power of Azotohacter 

 chroococcum and A. Beijerinckii is stimulated by the presence of 

 minute quantities of ammonium sulphate. In solutions containing 

 both dextrose and cellulose, mixed cultures of A. chroococcum and 

 Bacillus rossicus were more efficient than Azotohacter alone, if the 

 solution contained a considerable quantity of initial nitrogen, and a 

 destruction of the cellulose occurred. — S. E. W. 



Nola "gracilis [Bot. Mag. tab. 8541). — Asia Minor and Balkan 

 Peninsula. Nat. Ord. Violaceae, Tribe Violeae. ,Herb, inch 



high. Leaves f inch long, ovate oblong, with tapering base. Corolla 

 violet, Hmb i J inch long and i inch wide. — G. H. 



