THE GYMNCECIUM. 153 



Fig. 55. Fig. 56. 



rig. 56. Vertical section of tlie tricarpellary ovary of Spergularia rubra, a plant 

 belonging to the duckweed family, showing the attachment of the OTuIes to a free 

 central placenta. 



verse section of the trilocular or three-celled ovary of the Ery- 

 thronium. The ovules are attached to a central placenta. In 

 this instance the compound character of the ovary is sufficiently 

 evident. 



In the chickweed family, Fig. 56, the dissepiments at first 

 project across the cavity of the ovary and meet in its centre, 

 but are finally torn asunder by the expansion of the ovary, so 

 that the several loculi communicate, the ovules remaining 

 attached to the placentas in the middle. The vestiges of the 

 dissepiments remain attached to the walls of the ovary, proving 

 that this is the mode in which free central placentations are 

 produced. In the blood-root and violet, the placenta are strictly 

 parietal. 



In most cases the compound pistil, provided with a one-celled 

 ovary, is easily recognized. Thus every time that an unilocular 

 ovary is surmounted by several free styles and stigmas, or by 

 the same united amongst themselves and only distinguishable 

 at their summit by some slight incision, the pistil will be com- 

 pound. It is only necessary to remember that a pistil is never 

 without an ovary and stigma, and in most cases possesses a 



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