REFERENCES 17 



10. Kerr, T., and Bailey, I. W., The Cambium and Its Derivative 

 Tissues, X. Structure, optical properties and chemical com- 

 position of the so-called middle lamella. Jour. Arnold Arb. 

 15:327-349. 1934. 



11. Livingston, L. G.. The Nature and Distribution of Plasmodes- 

 mata in the Tobacco Plant. Amer. Jour. Bot. 22 :75-87. 1935. 



12. Meeuse, A. D. J.. Plasmodesmata. Bot. Pvev. 7 :249-262. 1941. 



13. Quisumbing', E.. Continuity of Protoplasm in Endosperm 

 Cells of Diospyros. Bot. Gaz. 80:439-449. 1925. 



14. Sharp, L. W., Introduction to Cvtology. 3rd ed. New York. 

 1934. 



15. van Wisselingh. C, Die Zellmembran. Handbuch d. Pflan- 

 zenanatomie. III. Berlin, 1924. 



