THE ANGIOSPERMAE 



387 



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Fig. 1288. — Progressive reduction of the gynoecium in certain parasitic genera. 

 A, Thesium. B, Santahim. C, Viscum. D, Scurnda. E, Tupeia. F, Balnno- 

 phora. {After Fat'ciliiuL E after Smart.) 



of Structure exist. Nucellus and integument are completely free from each 

 other except at the base. In addition to the ring of bundles in the integu- 

 ment there is a central strand of elongated cells from the base of the nucellus 

 up to the base of the embryo sac (Fig. 1289). There are no wall-thickenings 

 and the strand has no connection with the true vascular tissue in the chalaza. 

 One or two other isolated examples of similar axial strands of elongated cells 

 in the nucellus have been recorded, e.g., in Butomus umbeUatus and in Acacia 

 haileyana, where, however, the strand is connected, unlike that in Mynca, 

 to the vascular bundle of the funicle. 



