THE CARPEL 



247 



inferior ovaries. As with other advances, the development of the inferior 

 ovary has followed more than one line in structural modification. Fusion 

 of adjacent organs is a common feature of speciaHzation, and nearly all 

 inferior ovaries seem to have been formed in this way; in only a few 



Fig. 95. Diagrams of longitudinal sections of inferior ovaries A, C, E, and pseudo- 

 inferior ovaries, B, D, showing axial nature in vascular structure; stelar bundles 

 continuing to top of ovary, turning inward and downward sharply and ending in 

 center of floral cup; traces to ovules derived from down-running, inverted stelar 

 bundles. In B and D, ovules incompletely closed by stelar sheath. A, Darbya um- 

 bellulata; B, Rosa sp.; C, Pereskia hlco; D, Calijcanthus occidcntalis; E, Opuntia 

 dillenii.' (A, B, after Smith and Smith, B, adapted from Jackson; C, E, after 

 Tiagi. ) 



families has it been shown to be formed by a "sinking of the gynoecium 

 in the receptacle" — Santalaceae, Cactaceae (Fig. 95). 



Though the appendicular theory seems to be generally accepted in 

 America as correctly interpreting the great majority of inferior ovules. 



