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JOUENAL OF THE ROYAL HORTICULTURAL SOCIETY. 



In both there is an external foHar expansion associated with chorisis 

 of the cords of the ribs or veins induced by hypertrophy. 



The homology, then, of a normal ovule appears to be complete witli 

 abnormal cresting or foliaceous outgrowths.* 



Ovules, therefore, are not strictly speaking metamorphosed buds, as 

 they have been sometimes spoken of ; but really outgrowths from a fibro- 



FiG. 114. — Malformed and foliaceous ovules of Mignonette. 



vascular cord induced to grow out by hypertrophy of the foliar margins 

 when forming the placentas. 



Conclusion. — The object of the present Paper is to group together a 

 number of different facts and so bring them under one common cause ; 

 though it is impossible at present to explain how the general term 

 "hypertrophy " is connected with the branching of cords wdthin, and the 

 subsequent production of extra parts without, the plant. 



* For further details the reader is referred to the writer's work — Origin of Floral 

 Structures, p. 303. 



