THE FLOWER 



99 



mentioned above, marking the lines of junction of the 

 carpellary leaves, there are other lines or sutures which 

 mark the mid-ribs of the carpellary leaves. The latter 

 sutures are known as the dorsal or 

 back sutures, and the former as ven- 

 tral or face sutures (see fig. 90). 

 These sutures are very prominent on 

 the fruit or pod of Pea (fig. 91). They 

 are two in number, one ridged or 

 keeled and the other grooved. The 

 grooved suture, v, is ventral, as inside 

 it lies the placenta bearing seeds, and 

 the keeled suture, d, is dorsal. When 

 we shell the pod we generally do it 

 along the dorsal suture. 



When the parietal placentas project 

 considerably inwards towards the 

 centre of the ovary, without meeting 

 and cohering in the centre, the ovary 

 is said to be chambered, as in Poppy, shial-kanta, 

 and Orobanche. If, however, the projecting placentas 

 meet and cohere in the centre of the ovary, the ovary 

 no longer remains one- 

 celled, but becomes 

 divided into as many 

 cells or loculi as there 

 are carpels, and the 

 placentas no longer 

 lie on the wall, but 

 come to the centre of 

 the ovary, where they 

 cohere. Such ovaries 

 are then syncarpous, multilocular, with axile or cen- 

 tral placentation (fig. 92), as in Orange, Lemon, 

 dhanrhas [Hibiscus esculentus). The partition walls 



Fig, 91.— Pod 

 (legume) of Pea 



V, Ventral suture. 

 d. Dorsal suture. 



Figf. 92. — Transverse Section of Three-celled 

 Ovary with Central or Axile Placentation 



a, Dorsal suture, b. Ventral suture. 

 p, Placenta. 



