2 The Nature and Origin of Stipules. 



The results of my investigations are herewith given to the pub- 

 lic with the conviction that conclusions arrived at in the manner 

 indicated cannot fail of interest to the reader, nor, in some de- 

 giee at least, of scientific value. 



Columbia University, 



New York, Feb. 8, 1897. 



Synopsis. 



A Review of important Literature pertaining to Stipules 3 



The Nature and Origin of Stipules : — 



The Field of Enquiry defined 22 



Theoretical Discussion of the Primitive Leaf 23 



The three Types of Leaf-development as regards the Formation of 

 Stipules : 



a. When all the Parts develop as a Unit 29 



b. When a sheathing Petiole, Ligule, or Ochrea is formed 32 



c. When Stipulesare formed 37 



Conclusions 48 



