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MORPHOLOGY OF GYMNOSPERMS 



ripheral region contains a tangle of long, tortuous, and branching 

 suspensors, which are difficult to trace. During the formation of the 

 suspensor by the fertilized egg, free nuclear division takes place, 



Figs. 456-458. — Gnetutn Gtiemon: development of embryo; fig. 456, a proembryo 

 showing the branching, suspensor-like elongation of the egg, with free nuclei and 

 cleavage walls; also the embryonal cell containing a nucleus and numerous starch 

 grains; sections of other suspensors shown, and also a small portion of the undestroyed 

 tip of the nucellus; X40; fig. 457, beginning of embryo-formation by the embryonal 

 cell, showing free nuclei and the beginning of a cleavage wall; a cleavage wall in the 

 suspensor is also shown; X250; fig. 458, an embryo reconstructed from several sec- 

 tions, showing free nuclei, cleavage walls, and the beginning of uninucleate cells; 

 X140. — After Coulter (25). 



resulting in a few nuclei (four in some cases) distributed along the 

 suspensor (fig. 456). Usually between these nuclei transverse walls 

 are formed by the development of cleavage plates from the wall of 

 the suspensor. A cell at the tip of the suspensor is cut off in the same 



