2l6 



BOTANICAL GAZETTE 



[march 



(fig. i) and measures 10 to 20 cm in length and 7 to 



n cm in 



diamet 



At the time of 



shedding the 



toon 



Fig. i. —Upper portion of plant of D 

 edule with staminate cone. Photographed 

 at Chavarrillo, Mexico, September, 1906. 

 One-third natural size. 



pollen, the axis of the 

 cone elongates considerably 

 and becomes so weak that 

 it bends over until its tip 

 rests upon the leaves of the 

 crown. Insects are very 

 numerous in nearly all the 

 mature staminate cones, but 

 none were found on the ovu- 

 late cones, and although the 

 insects were throughly dusted 

 with pollen, there was nothing 

 further to indicate that any 

 pollination was being effected 

 through their agency. 



MICROSPORANGIA 



staminate 



are long and 

 and end in 



wedge 

 a single 



-shaped 

 ;harp 

 ward 

 osed, 



point which curves up 

 (fig. 2) . The outer, exp 

 abaxial faces of the sporo- 

 phylls are densely hairy, but 



the upper faces are 



quite 



smooth. In the sporophyfc 

 of the upper and lower por 



tions of the cone, a 



sterile 



line divides the sporangia 



into 



(fig 



hile m 



median 



rangia cover the entire under- 

 surface. The sporophylls are 

 so crowded in the cone tha 



distinct 



the 

 im- 



sporangia on the under side of a sporophyll make a 



pression upon the upper side of the sporophyll immediately below i • 



