154 MORPHOLOGY AND LIFE HISTORY 



the presence or absence of a petiole. Describe 

 accurately the vernation (condition in the bud), as 

 shown by young leaves just unfolding. 



2. Suggest any advantage to the plant of any of the 

 facts recorded under D, i. 



3. Compare the character of the leaves with that of 

 any of the ferns. 



E. The Roots: 



i. Briefly state their location and functions. 



REPRODUCTIVE ORGANS 



F. The Staminate Cones: 



1. Describe their appearance, and, if the material is 

 suitable, their distribution on the plant. 



2. Describe, accurately, the distribution of the micro- 

 sporophylls (stamens) on the main axis, or stem, of 

 the cone. 



3. Make drawings, natural size, showing (a) a surface 

 view of the cone; (b) the cone as seen in longitudinal 

 section? 



4. Remove one of the stamens. Describe it, and note 

 the microsporangia (pollen-sacs) attached to its 

 lower surface. Describe them, their number, dis- 

 tribution, mode of attachment, and manner of 

 opening (dehiscence) . 



5. Make drawings (a) of a stamen with pollen-sacs 

 attached; (b) of two or three pollen-sacs (X 10). 



6. The staminate cone is in reality a primitive flower. 

 From this study, of what structure would you infer 

 that flowers are a modification? 



G. The Male Gametophyte: 



i. The young pollen-grain (microspore) begins to 

 germinate before it leaves the pollen-sac, two divi- 



