200 



PLANT STKUCTUKES 



gether form a common ovary, while the styles may also 

 combine to form one style (Fig. 1G9, C), or they may remain 

 more or less distinct (Fig. 169, B). Such an ovary may 

 contain a single chamber, as if the carpels had united edge 

 to edge (Fig. 170, A) ; or it may contain as many chambers 

 as there are constituent carpels (Fig. 170, B), as though 

 each carpel had formed its own ovary before coalescence. 

 In ordinary phrase an ovary is either "one-celled" or 

 " several-celled," but as the word " cell " has a very differ- 

 ent application, the ovary chamber had better be called a 

 loculus, meaning "a compartment." Ovaries, 



FIG. 170. Diagrammatic sections of ovaries: A, cross-section of an ovary with one 

 loculus and three carpels, the three sets of ovules said to be attached to the wall 

 (parietal); B, cross-section of an ovary with three loculi and three carpels, the 

 ovules being in the center (central) ; O, longitudinal section of J5, showing ovules 

 attached to free axis (" free central "). After SCHIMPEB. 



therefore, may have one loculus or several loculi. Where 

 there are several loculi each one usually represents a con- 

 stituent carpel (Fig. 170, B) ; where there is one loculus 

 the ovary may comprise one carpel (Fig. 169, ^4), or several 

 (Fig. 170, A). 



There is a very convenient but not a scientific word, 

 which stands for any organization of the ovary and the 

 accompanying parts, and that is pistil. A pistil may be 

 one carpel (Fig. 169, A), or it may be several carpels or- 

 ganized together (Fig. 169, B, (7), the former case being a 

 simple pistily the latter a compound pistil. In other words, 



