312 MINNESOTA BOTANICAL STUDIES 



67. Thornber, J. Studies in the vegetation of the State I. The 

 Prairie-grass formation in region I. Bot. Surv. Neb. 1901. 



68. Vinall, H. N. Forage crops for the sandhill section of Ne- 

 braska. U. S. Dept. Agri., Bur. Plant Ind., Circ. 80. 1911. 



69. Warren, J. A. Notes on the number and distribution of native 

 legumes in Nebraska and Kansas. U. S. Dept. Agri., Bur. Plant 

 Ind., Circ. 31. 1909. 



70. . An agricultural survey of Nebraska. Ann. Rep. 



Neb. State Board Agri., 1909. 



71. Warming, E. Oecology of plants. 1909. 



72. Webber, H. J. Grasses of central Nebraska. Ann. Rep. 

 Neb. State Board Agri. 1889. 



72). . The flora of central Nebraska. Am. Nat. 23:633. 



1889. 



74. . The freshwater algae of the plains. Am. Nat. 



23:1011. 1889. 



75. . Appendix to catalogue of the flora of Nebraska. 



Trans. St. Louis Acad. Sci. 6: No. 1. 1892. 



76. Webber, H. J., and Bessey, C. E. Report of the botanist on 

 the grasses and forage plants, and the catalogue of plants. Ann, 

 Rep. Neb. State Board Agri. 1889. 



77 . Wolcott, R. H. Biological conditions in Nebraska. Sixteenth 

 Ann. Pres. Address, Neb. Acad. Sci. 



78. . An analysis of Nebraska's bird fauna. Studies 



from the Zoo. Lab. Uni. Neb., No. 99. 1909. 



