- 21 - 



15. H, C. Sorby, Proc. Roy, Soc, 21^, I4U2 (1875). 



li;. M, Tswett, Ber. deut, botan. Ges., 2^, 58U (I9O6). 



15. H, Ho Strain, J. Biol. Chem,, 10^ , 525 (19314.). 



16. H. Ho Strain, W. M. Manning, and G. Hardin, Biol. Bull., 86, I69 



(1914+). 



17. W, G„ Brown, Nature, li+5, 577 (1959). 



18. H, F„ Linskens, Ed., Papierchromatographie in der Botanik. Springer, 

 Berlin, GBttingen, Heidelberg, 1955o 



19„ H. H. Strain, J. Phys, Chem., 57, 658 (1953). 



20. H. H„ Strain and T. R„ Sato, In, A conference on radioactive iso- 

 topes in agricult\ir©, January 12-li4., 1956. p. 175* U.S. Atomic 

 Energy Commission Report Number TID-7512o 



