338 THE STRUCTURE OF ECONOMIC PLANTS 



14. Graber, L. F., Nelson, N. T., Leukel, W. A., and Albert, W. B., "Organic 



food reserves in relation to the growth of alfalfa and other perennial herba- 

 ceous plants." Wise. Agr. Exp. Sta. Res. Bull. 80, 192.7. 



15. Jones, F. R., "Winter injury of alfalfa." Jour. Agr. Res. 57.- 189-111, 19x8. 



16. JosT, L., "Uberdie Selbststerilitat einiger Bliiten." Bot. Zeit. 6j.- 77-117, 1907. 



17. LeClerg, E. L., and Durrell, L. W., "Vascular structure and plugging of 



alfalfa roots." Colo. Agr. Exp. Sta. Bull, j^g, 1918. 



18. Lute, Anna M., "Impermeable seed of alfalfa." Colo. Agr. Exp. Sta. Bull. 



}26, 19Z8. 



19. Martin, J. N., "Comparative morphology of some Leguminosae." Bot. 



Gaz- s8: 154-167, 1914. 

 io. , "Relation of moisture to seed production in alfalfa." Iowa Agr. 



Exp. Sta. Res. Bull. 2_j, 191 5. 

 ■Li. MiLOviDov, P., "Uber einige neue Beobachtungen an den Lupinenknoll- 



chen." Centhl. Bakt. (jtc.'), 2 Abt., 68: 333-345, 1916. 

 ii. , "Recherches sur les tubercles du lupin." Rev. Gen. Bot. 40: 1-13, 



192.8. 

 13. Nageli, C, Beitrdge %ur Wissenschaftlkhen Botanik, Part I, Engelmann, Leipzig, 



1858. 

 24. Pammel, L. H., "Anatomical characters of seeds of Leguminosae, chiefly 



genera of Gray's Manual." Trans. Acad. Set. St. Louis, q: 91-174, 1899. 

 15. Piper, C. V., Evans, M. W., McKee, R., and Morse, W. J., "Alfalfa seed 



production; pollination studies." U. S. Dept. Agr. Dept. Bull. 7/, 1914. 

 z6. Reeves, R. G., "Nuclear and cytoplasmic divisions in the microsporogenesis 



of alfalfa." Am. Jour. Bot. ly: 19-40, 1930. 

 2.J. , "Development of the ovule and embryo sac of alfalfa." Am. Jour. 



Bot. ij: 139-146, 1930. 

 i8. Rimbach, a., "Die Wirkung der Wurzelverkiirzung bei einigen Nutz- und 



Zierpflanzen." Angew. Bot. 4: 81-90, 1911. 

 19. Stewart, G., Alfalfa Growing in the United States and Canada, The Macmillan 



Co., 1916. 



30. Thornton, H. G., "The early development of the root nodule of lucerne 



(Medicago sativa L.)." Ann. Bot. 44: 385-391, 1930. 



31. , "The influence of the host plant in inducing parasitism in lucerne and 



clover nodules." Proc. Roy. Soc. London, Ser. B, 106: iio-iii, 1930. 



31. VAN Tieghem, p., "Recherches sur la symctrie de structure des plantes vascu- 

 laires." Ann. Sci. Nat., Bot. Ser. V, i}: 5-314, 1871. 



33. Weaver, J. E., Root Development of Field Crops, McGraw-Hill Book Co., 1916. 



34. Westgate, J. M., "Variegated alfalfa." U. S. Dept. Agr. Bur. Plant Ind. 



Bull. 169: 1-63, 1910. 



35. Wilson, O. T., "Studies on the anatomy of alfalfa (Medicago sativa L.)." 



Kan. Univ. Sci. Bull, j: 191-199, 1913. 



36. Winter, Clara W., "Vascular system of young plants of Medicago sativa." 



Bot. Gaz. 94: 151-167, 1931. 



37. WiNTON, Kate B., "Comparative histology of alfalfa and clovers." Bot. 



Gaz- 57: 53^63, 1914. 



