98 MORPHOLOGY 



carpels, the pistil in both being composed of two 

 carpels. 



The manner in which the carpellary leaves cohere 

 with one another to give rise to the syncarpous con- 

 dition is different in different classes of plants. The 

 carpellary leaves which stand in a whorl may cohere 

 by the adjacent margins, so as to form one ovary 

 with one chamber or cell, the lines of junction or 

 SUTURES of the carpellary leaves being as many as 

 the number of the leaves. These sutures are usually 

 a,. marked on the outer surface of the 



wall of the ovary by a line or groove, 

 and on the inner surface of the wall 

 by a more or less projecting struc- 

 ture. These projecting structures 

 Fig. 9.. -Transverse inside the ovary are known by the 

 Section of a One-celled ^^^^ ^f PLACENTA, and thesc placen- 



Ovary with Farietal ' ^ 



piacentation tas are dcstined to bear ovules. If 



a, Dorsal suture. wc make a cross-sectioH of the ovary 



h. Ventral suture. c • u c n / c ^<_\ 



A Placenta. Of fruit of a Papaw (see fig. 77), we 



find that the ovary is composed of 

 three to five carpels, is syncarpous, one-celled or uni- 

 locular, with three to five placentas on the inner sur- 

 face of the wall bearing ovules. Similarly, if we 

 examine the ovary of jhumka-lata or Passion Flower, 

 we find the same thing, namely, that it is composed 

 of three carpels, is syncarpous, unilocular, with three 

 placentas on the inner wall bearing ovules. The 

 ovary of natkan or Anatto discloses that it is com- 

 posed of two carpels, and is syncarpous, unilocular, 

 with two placentas on the inner wall bearing ovules. 

 If the placentas are on the wall of the ovary, as in the 

 instances given above, they are said to be parietal 

 (on the wall) (fig. 90), and such a mode of piacentation 

 . is called parietal piacentation. Besides the sutures 



