246 REFERENCES: HORTICULTURE 



SOILS 



Alway, F. J., and Bishop, E. S. Nitrogen content of the humus of arid soils. 



Journal of Agricultural Research, 5: 909-916. February 14, 1916. 

 Brown, P. E. Relation between certain bacterial activities in soils and their crop- 

 producing power. Journal of Agricultural Research, 5: 855-870. January 



31, 1916. 

 Bouyotjcos, G. J. Effect of temperature on the movement of water vapor and capil- 

 lary moisture in soils. Journal of Agricultural Research, 5: 141-172, figs. 



1-11. October 25, 1915. 

 Giltner, Ward, and Langworthy, H. Virginia. Some factors influencing the 



longevity of soil micro-organisms subjected to desiccation, with special reference 



to soil solution. Journal of Agricultural Research, 5: 927-942. February 



14, 1916. 

 Koch, G. P. Soil Protozoa. Journal of Agricultural Research, 4: 511-560. 



September, 1915. 

 Koch, G. P. Activity of soil Protozoa. Journal of Agricultural Research,' 5: 



477-488. December 13, 1915. 

 Kopeloff, Nicholas, Lint, H. C., and Coleman, D. A. Separation of soil 



Protozoa. Journal of Agricultural Research. 5: 137-140. October 18, 1915. 

 LeClair, C. A. Influence of growth of cowpeas upon some physical, chemical, and 



biological properties of soil. Journal of Agricultural Research, 5:439-448, 



figs. 1-2, pi. 42. December 6, 1915. 

 Oskamp, Joseph. Soil temperatures as influenced by cultural methods. Journal 



of Agricultural Research, 5: 173-180, figs. 1-4. October 25, 1915. 

 Plummer, J. K. Petrography of some North Carolina soils and its relation to 



their fertilizer requirements. Journal of Agricultural Research, 5: 569-582, 



pi. 52. December 27, 1915. 



BOTANY 



Hedgcock, G. G. Parasitism of Comandra umbellata. Journal of Agricultural 

 Research, 5: 133-136. October 18, 1915.' 



Mason, S. C. Botanical characters of the leaves of the date palm used in dis- 

 tinguishing cultivated varieties. U. S. Department of Agriculture, Bulletin 

 No. 223. Pp. 1-28. June 23, 1915. 



Piper, C. V., and Morse, W. J. The bonavist, lablab, or hyacinth bean. U. S. 

 Department of Agriculture, Bulletin No. 318. Pp. 1-15. November 18, 1915. 



Sudworth, G. B. The spruce and balsam fir trees of the Rocky Mountain region. 

 U. S. Department of Agriculture, Bulletin No. 327. Pp. 1-43. February 19, 

 1916. 



Westgate, J. M., Coe, H. S., Wiancko, A. T., Robbins, F. E., Hughes, H. D., 

 Pammel, L. H., and Martin, J. N. Red-clover seed production: pollination 

 studies. U. S. Department of Agriculture, Bulletin No. 289. Pp. 1-31. 

 September 21, 1915. 



HORTICULTURE 



Coville, F. V. Directions for blueberry culture, 1916. U. S. Department of 

 Agriculture, Bulletin No. 334. Pp. 1-16. December 28, 1916. 



