SIMPLE AND COMPOUND OVARY. 279 
Having now described the parts, nature, and structure of 
the carpel, and of the gyncecium or pistil generally, we proceed 
in the next place to allude separately to the constituent parts of 
the carpel, both in a free and combined state, namely, the ovary, 
style, and stigma. 
1. THe Ovary.—The ovary, as already mentioned (page 
275) is called compound when it is composed of two or more 
ovaries combined together ; or, on the contrary, it is simple 
when it constitutes the lower part of asimple pistil (jig. 583, 0), 
or of one of the carpels of an apocarpous pistil (fig. 581). It 
should be noticed, therefore, that the terms simple pistil and 
simple ovary are not in all cases synonymous terms; thus, a 
pistil is only said to be simple (jigs. 583 and 603), when it is 
Fic. 624. 
Fic. 625. Fic. 626. 
Fig. 624. Pistil of Dictamnus Frazvinella. The ovary is supported on a gyno- 
phore, g, and is superior.— Fig. 625. Vertical section of the flower of 
a Saxifrage, showing the ovary partially adherent to the calyx. Fig. 
626. Compound irregular mature ovary of Antir7hinum. 
formed of but one carpel, the terms pistil and carpel being then 
mutually convertible ; but an ovary is simple, as just noticed, 
whether it forms part of a simple pistil, as in Leguminous 
plants generally (jig. 603), or of one of the carpels of an 
apocarpous pistil, as in the Stonecrop (jig. 581). An ovary is 
also said to be monomerous when it is formed of only one 
carpel ; or dimerous, trimerous, tetramerous or polymerous when 
it is formed by the coherence of two, three, four, or many 
carpels. 
Generally speaking, the ovary is sessile upon the thalamus, 
the carpellary leaves out of which it is formed having no stalks. 
In rare cases, however, the ovary is more or less elevated above 
the outer whorls, when it is said to be stalked or stipitate, as in 
the Dictammus (fig. 624, g), and Dianthus (fig. 602, g); this 
stalk has received the name of gynophore. We shall refer to the 
gynophore again under the head of Thalamus (page 292). 
