290 



OEGAXOGEAPHT. 



should correspond with it in structiire. This is the case generally, 

 and we find the fruit therefore consisting of the same parts 

 as the ovary, only in a modified condition ; thus, the walls of 

 the ovary commonly alter in texture, and either become dry, 

 membranous, coriaceous, woody, &c. ; or, on the contrary, more 

 or less pulpy, fleshy, &c. 



At other times more important changes take place during the 

 ripening of the ovary, which disguise the real structure of the 

 fruit. These changes either arise from the addition, abortion, 

 or alteration of parts. Thus, 1st. The addition of parts is 

 commonly produced by the formation of the spurious dissepiments 

 already alluded to. In Datura Stramonium, for instance, we 

 have a two-celled ovary converted into an imperfectly four-celled 

 fruit, by the formation of a spurious vertical dissepiment {figs. 

 602 and 603) ; this dissepiment appears to be formed by the pro- 

 jection of the placentas on the two sides, which meet and become 

 united to corresponding projections from the dorsal sutures. In 

 Cassia Fistula, again (fig. 600), and some other fruits of a 

 similar nature, we have a one-celled ovary converted into a many- 

 celled fruit, by the formation of a number of transverse dissepi- 

 ments. In Pretrea zangueharica, a one-celled ovary is con- 

 verted into a six-celled fruit {Jig. 644), by an extension and 

 doubling inwards of the placenta. In Tribuhis terrestris, the 

 ovary is quinquelocular, but as it approaches to maturity, each 

 loculus {figs. 645 and 646) becomes divided into as many divi- 



Fig. 644. 



Fig. 646. 



Fig. 644. Transverse section of 

 the fruit of the Pretrea zan- 

 gueharica. From Llndley. 

 Fig. 645. A vertical sec- 

 tion of a loculus of the ovary 

 of Tribulus terrestris. o, o, o. 

 Ovules, c. Projections from 

 the wall whlcJi are commen- 

 cing to separate the ovules. Fig. 646. A vertical section of the loculus of 



a ripe ovary of the same, in which the partitions, c, completely separate the 

 seeds, g. 



sions as there are seeds contained within it, in consequence of 

 a corresponding number of projections from its walls. Other 

 examples of the formation of spurious dissepiments producing 

 changes in the ovary have been already mentioned when speaking 

 of these processes (see page 271). 



2nd. Other alterations are produced by the abortion or ob- 



