184 MORPHOLOGY AND LIFE HISTORY 



detailed study may be made of the structure of the 

 pollen-grain. 

 H. The Young Carpellate Cone: 



1. On which internode of the vegetative branch are 

 the carpellate cones borne? On what part of the 

 branch? Do they occur singly or in clusters? As 

 terminal or as lateral outgrowths? 



2. Note that each carpellate cone is borne at the tip 

 of a stalk. Describe any outgrowths on this stalk. 



3. Describe the attitude of the cone at the time of 

 pollination, as erect or pendant. 



4. Observe the spiral arrangement of the cone-scales, 

 somewhat more marked than in the staminate cone. 

 In fresh specimens the cone-scales are slightly 

 separated from each other at the time of pollina- 

 tion. Explain the advantage of this. 



5. Make a drawing (X 2) of the cone with the stalk 

 that bears it. 



6. Make a median longitudinal section of the cone and 

 stalk, and represent by a drawing all parts seen. 



7. Carefully dissect off one of the central cone-scales, 

 being sure to note which is the inner (ventral) and 

 which the outer (dorsal) surface of the scale, and 

 observing the membranous bract which subtends it. 



8. On the inner surface of the scale, near the base, 

 observe with the hand lens two ovules, each with 

 two little prongs, between which is the pollen- 

 chamber; between and above the ovules a pointed 

 outgrowth. 



9. Make drawings (X 10) of the ovuliferous scale as 

 seen (a) from the side; (b) from the outer surface, 

 showing the bract; (c) from the inner surface, 

 showing the ovules. 



