626 EXPERIMENT STATION RECORD. [Vol.35 



The surface consists of a high rolling plain, deeply dissected by flowing streams. 

 The topography of the plain is undulating to gently rolling, while that of the 

 lowland is hilly. Including rough broken land and dune sand, 22 soil types of 

 eight series are mapped, of which the Vernon clay loam and very fine sandy 

 loam cover 19 and 9.2 per cent of the area, respectively, rough broken land 11.8, 

 and the Richfield fine sandy loam 10.1 per cent. 



Soil survey of Lancaster County, Pennsylvania, B. D. Gii^ert, W. B. Cobb, 

 E. L. MoFFiTT, and J. F. Cox (U. S. Dept. Agr., Advance Sheets Field Operations 

 Bur. Soils, 1914, pp. 70, fig. 1, map 1). — This survey, made in cooperation with 

 the Pennsylvania College and Station and issued July 21, 1916, deals with the 

 soils of an area of 602,240 acres in southeastern Pennsylvania which " consists 

 of a central valley or lowland occupying about 50 per cent of its total area, 

 surrounded on all sides by highland, except where narrow belts of the lowland 

 project from the main area and extend to or beyond the county line." The 

 regional drainage is mature and complete. 



The soils of the county are residual and alluvial in origin and the loams and 

 silt loams predominate, including rough stony land and meado\#. Thirty-six 

 soil types of 17 series are mapped, of which the Hagerstown silt loam and the 

 Manor loam cover 24 and 20.6 per cent of the area, respectively. 



Soil survey of Brazos County, Texas, J. O. Veatch and C. S. Wai^dbop 

 (U. S. Dept. Agr., Advance Sheets Field Operations Bur. Soils, 1914, PP- 53, 

 fig. 1, map 1). — This survey, made in cooperation with the Texas Experiment 

 Station and issued July 10, 1916, deals with the soils of an area of 369,920 acres 

 in east-central Texas lying in the Gulf Coastal Plain. The topography is level 

 to gently rolling and the greater part of the county is well drained. 



The county " embraces a rather wide range of soils, having peculiar differ- 

 ences in texture, structure, drainage, or other characteristics, which . . . affect 

 in some degree crop yields and the ease or difficulty of cultivation. . . . Two 

 general groups are recognized, (1) the upland soils and (2) the bottom land 

 and terrace soils. The upland soils are mainly derived from underlying sedi- 

 mentary deposits. The bottom and terrace soils are alluvial." Thirty soil types 

 of 13 series are mapped, of which the Lufkin and Susquehanna fine sandy loams 

 cover 40.3 and 11.3 per cent of the area, respectively. 



Soil bacteriology, C. M. Hutchinson (Rpt. -Agr. Research Inst, and Col. 

 I'usa, 1914-15, pp. 79-89; Ami. Rpt. Bd. Sci. Advice India, 1914-15, pp. 110- 

 116). — Continuing work previously reported (E. S. R., 33, p. 513), it was found 

 in studies of bacteriotoxins in soils that "the inhibition of nitrification occur- 

 ring in soils under water-logged or semianaerobic conditions was not due merely 

 to lack of oxygen required for formation of the completely oxidized product, but 

 to the action of toxins resulting from the activity of certain classes of bacteria 

 which rapidly multiply under these conditions. ... It was found that such 

 toxins result from decomposition of organic nitrogen compounds by bacterial 

 action under semianaerobic conditions, and further proof that the inhibition of 

 nitrification is not due merely to shortage of oxj'gen was afforded by the obser- 

 vation that, vpith the same air supply as was sufficient for complete nitrification 

 of ammonium sulphate in soil, nitrification of oil cake containing the same 

 amount of nitrogen was completely inhibited. . . . 



" It was found in actual practice in the field that germination in a soil which 

 had been water-logged was Interfered with and that the ensuing crop was con- 

 sequently poor, nor was this remedied by application of nitrate of soda, although 

 the use of superphosphate was successful. Laboratory experiments showed that 

 rapid reduction of nitrate takes place in water-logged soU, a large proportion of 

 nitrite being formed. ... It was found in the laboratory that superphosphate 



