468 BOTANY OE CROP PLANTS 



Pammel, Edna C, and Clark, Clarissa: Studies in Variation of Red Clover. 



Proc. la. Acad. Sci., 18: 47-53, 1911. 

 Pammel, L. H., and King, Charlotte M.: Pollination of Clover. Proc. la. 

 Acad. Sci., 18: 35-45, 1911. 

 Pollination of Clover. Contrib. Bot. Dept. la. State College, 47: 1-45, 1911. 

 Peenninger, Ues. : Untersuchung der Fruchte von Phaseolus vulgaris L. in 

 verschiedenen Entwickelungstadien. Ber. Deut. Bot. Ges., 27: 227-234, 

 1909. 

 Piper, C. V., and Morse, W. J.: The Soybean; History, Varieties, and Field 

 Studies. U. S. Dept. Agr. Bur. Plant Ind. Bull. 197: 1-84, 1910. 

 Five Oriental Species of Beans. U. S. Dept. Agr. Bull. 119: 1-32, 1914. 

 The Bonavist, Lablab, or Hyacinth Bean. U. S. Dept. Agr. Bull. 318: 



1-15- 1915- 

 The Soy Bean, with Special Reference to Its Utilization for Oil, Cake and 



Other Products. U. S. Dept. Agr. Bull. 439: 1-20, 191 6. 

 Piper, C. V.: Agricultural Varieties of the Cowpea and Immediately Related 



Species. U. S. Deot. Agr. Bur. Plant Ind. Bull. 229: 1-160, 1912. 

 Soja Max. Jour. Am. Soc. Agron., 6: 75-84, 1914. 

 Piper, C. V., Evans, Morgan W., McKee, Roland, and Morse, W. J.: 



Alfalfa Seed Production; Pollination Studies. U. S. Dept. Agr. Bull. 75- 



1-32, 1914. 

 Piper, C. V., and McKee, Roland: Vetches. U. S. Dept. Agr. Farmers' 



Bull. 515: 1-28, 1912. 

 ScoriELD, Carl S.: The Botanical History and Classification of Alfalfa 



U. S. Dept. Agr. Bur. Plant Ind. Bull. 131: 1-1-19, 1908. 

 Shaw, Thomas: Canadian Field Peas. U. S. Dept. Agr. Farmers' Bull. 224: 



1-16, 1905. 

 Tracy, W. W.: American Varieties of Garden Beans. U. S. Dept. Agr. Bur. 



Plant Ind. Bull. 109: 1-173, 1907. 

 Westgate, J. M.: Variegated Alfalfa. U. S. Dept. Agr. Bur. Plant Ind. Bull. 



169: 1-63, 1910. 

 Westgate, J. M., and Hillman, F. H.: Red Clover. U. S. Dept. Agr. 



Farmers' Bull. 455: 1-48, 1911. 

 Westgate, J. M., and Vinall, H. N.: Sweet Clover. U. S. Dept. Agr. 



Farmers' Bull. 485: 7-39, 1912. 

 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. Dept. Agr. Bull. 289: 1-31, 1915. 

 Wight, W. F.: The History of the Cowpea (Vigna unguiculata) and Its 



Introduction into America. U. S. Dept. Agr. Bur. Plant Ind. Bull. 102: 



43-59, 1907- 

 Winton, Kate, B.: Comparative Histology of Alfalfa and Clovers. Bot. 



Gaz., 57: 53-63, 1914. 



