48 



This embonpoint now rapidly increases in height, and inwards, towards 

 similar features on the corresponding opposite sporophyll, and finally, they all 

 valvate, the three larger meeting in what is now the apex of the cone, and 

 together with the three lower or smaller ones form a ca\-ity OA-er and 

 enclosing the fertilised ovules, or zygotes. 



> 



Figure 27. — I">i.ier.imm-T»ir ^-rji-^ showing the origin of the "spur" on the valves of tlic cone, the process being 



arrows from Figure .-X to Figure K. 



m;irli0d by the 



The original free end of the sporojilnll has in tlie meantime become less 

 and less prominent, as it recedes from tlie newly formed ape.x, and finally exists 

 only as a spur or dorsal point towards the top of eacli \ah-e, as in C. calcarata, or 

 C. glauca ^Figure 27 k), respectively, whilst in C. oblonga its absorption into the 

 scale has been less, and so is a prominent svstematic character in that species. 



This phenomenon can be traced in Pines other tlian .Australian. 



Figures 28 to 2t2> reproduce a longitudinal series from original material 

 intended to illustrate this gradual thickening of the spc)r(ii)liylls at their lower 

 middle, after fertiii.sation of the ovules, anrl which thickening can be traced 

 gradually, till it eventually forms a dome over the macrosporangia, whilst 



