280 



ORGANOGRAPHY. 



as in that just alluded to. This is produced, either by the union 

 of the contiguous margins of flattened carjiellary leaves, as 

 in the Mignonette (/?es«/a) (.^5/. 606), and Cactus (^^r, 616); 

 or by the union of carpels which are only partially folded in- 

 wards, so that all their cavities communicate in the centre, and 

 hence such a compound ovary is really unilocular, as in the 

 Orchis (fg. 607), and Poppy (Jig. 608). 



Having now described the parts, nature, and structure of the 

 simple carpel, and of the gynoecium, we proceed in the next 

 place to allude generally to their constituent parts; namely, the 

 ovary, style, and stigma. 



Fig. 606. Fig. 607. Fig. 608. 



Ft!}. BOG. Transverse section of the unilocular ovary of Mignonette (Reseda), 

 c. Carpels of which it is formed, pi. Parietal placentas Fi<j. GOT. Trans- 

 verse section of tlie unilocular ovary of an Orchis, c. Carpels, slightly in- 

 folded, pi. Placentas Fig. (\m. Transverse section of the ovary of a 



species of Poppy, or. Ovules. ;*/. Placentas, which in the young ovary al- 

 most meet in the centre, and thus it becomes almost multilocular, but as the 

 ovary progresses in development it is seen to be distinctly unilocular. 



1. The Ovary.— The ovary, as al- 

 ready defined, is called compound when 

 it is composed of two or more ovaries 

 combined together ; on the contrary, 

 it is simple when it constitutes the 

 lower part of a single pistil, or of one of 

 the carpels of an apocarpous pistil. It 

 should be noticed, therefore, that the 

 terms simple pistil, and simi)le ovary, 

 are not in all cases synonymous terms ; 

 thus, a pistil is only said to be simple 

 (figs. 568 and 588), when the gynoecium 

 is formed of but one carpel, the two 

 terms i)istil and cari)el being then mu- 

 tually convertible ; but an ovary is sim- 

 ple, as just noticed, whether it forms 

 part of a simple pistil, or of one of the 

 Fig. 609. Pistil of Dictam- carijcls of au apocarpous pistil. 



nus I-rttxnielUi. The X, ,, , • i • -i 



ovary is supported on a (lencrally spcakiug, thc ovary is sessile 

 u])on thc receptacle or thalamus, the 

 car])ellary leaves out of which it is 



pynophore, j/, and is su- 

 perior. 



