320 EXPERIMENT STATION RECORD. 



Recent investigations beiiriiig uiton (lie inU'ni'lation and interdependence 

 of plants and soil organisms are reviewed as indicating " tlie way along wliich 

 future research on soils must proceed." 



Enzymatic activities in soils, O. Scheeinek and M. X. Sullivan {Abs. in 

 Science, n. ser., 33 (I'Jll), No. SJ/'i, P- 339).— The author points out that 

 amylolytic, proteolytic, cytolytic, lipolytic, and inverting enzyms exist in the 

 soil. "The oxidizing and catalytic activities of the soil, comparable to the 

 same activities in plants and animals where it has been attributed to enzyms, 

 are especially noticeable and easy of demonstration. As yet no satisfactory 

 means have been obtained of extracting enzyms from soil to any great extent, 

 though in soils recently cropped there is some slight evidence of the presence 

 of enzyni-like substances in the glycerin extract of the soil." 



Two compounds isolated from peat soils, C. S. Robinson (Jour. Arner. 

 Chem. t^oc, 33 (1911), No. /^ pp. 567,-56'^). — The author isolated leucin and 

 isoleuciu from a sample of common brown peat. A sample of black peat was 

 also examined, but the material obtained was too small to permit a separation 

 of the isomers. 



The isolation of creatinin from soils, E. C. Shorey (Afts. in Science, n. ser., 

 S3 (1911), No. S.'i.'i, J). 3JfO). — Creatinin was isolated from various soils. The 

 method used is described in detail. 



Productivity of soils, F. H. King (Science, n. ser., 33 (1911), No. 851, pp. 

 61^-619). — This is a review of a paper by Chamberlin on the secular mainte- 

 nance of soils (E. S. R., 24, p. 709), in which exception is taken to certain 

 of the conclusions drawn in that paper, particularly those relating to the 

 maintenance of the supply of potash and phosphoric acid in the surface soil 

 as a result of the so<-alled capillary and plant cycles. 



Examination of soil samples (U. S. Dept. Agr., Bur. Soils Circ. 26, pp. 7). — 

 This circular outlines the procedure of the Bureau of Soils in examinations 

 of soil samples submitted by correspondents, discusses different factors which 

 must be taken into consideration in judging of the character and adaptation 

 of soils, and specifies the information that should accompany soil samples sent 

 to the Bureau for examination. 



Soils of the Eastern United States and their use. — III, The Portsmouth 

 sandy loam, J. A. Bonsteel (U. S. Dept. Agr., Bur. Soils Circ. 2-i, pp. 12). — 

 This, the third of this series of circulars, deals with the Portsmouth sandy 

 loam, of which a total area of 774,052 acres in 21 different areas in 9 States 

 has been surveyed by the Bureau of Soils. 



Soils of the Eastern United States and their use. — IV, The Sassafras silt 

 loam, J. A. Bonsteel (U. S. Dept. Agr., Bur. Soils Circ. 25, pp. i^).— This, the 

 fourth of this series of circulars, deals with the Sassafras silt loam, of which 

 a total area of 518,142 acres in four different States has been surveyed by the 

 Bureau of Soils. 



[Soils of the Hawaiian Islands], E. V. Wilcox (Hawaii Sta. Rpt. 1910, pp. 

 11, 12). — "The soils of the Hawaiian Islands are very different in several 

 respects from those which are familiar to farmers and agricultural workers on 

 the mainland. In the first place, the Hawaiian soils contain high percentages 

 of iron in various forms (say from 15 to 30 per cent). In addition to the high 

 iron content, the soils contain more titanium than mainland soils, and in some 

 localities also a iarge amount (up to 9 per cent) of manganese. The presence 

 of the large quantity of iron in Hawaiian soils gives them physical properties 

 which are seldom met wiih in soils on the mainland. Wherever special atten- 

 tion is not given to cultivation, the soils rapidly become impervious to water 

 and air, and the iron present iu the soil is reduced to the ferrous state. This, 

 as is well known, is injurious to plant growth and is instrumental in prevent- 



