244 



MANUAL OF BOTANY 



{fig. 519). The placentas bearing the seeds are here attached to 

 the axis, a, between the dissepiments, c, v. Septifragal dehis- 

 cence may be combined with either the loonlioidal or septioidal 

 form (figs. 520 and 518). 



In polyoarpellary fruits with one cell having parietal or free 

 central plaoentation, we have two forms of dehiscence ; these 

 correspond to the ordinary septicidal and loculioidal kinds just 

 described. Thus, in compound fruits with parietal placenta- 

 tion, the dehiscence may take place either through the confluent 

 margins or sutures of the adjoining carpels, so that each 

 placenta is divided into its two lamellas, as in the species of 



Fig. 522. 



Fig. 52.S. 



Pig. 524. 



Fig. 522. One-ceHed fruit of a species of Gentian deliisoing in a, septicidal 

 manner. — '—Fig. 623. Fmit of siliqua of the Wallflower, showing the 



separation of two valves from the replum. Fig. 524. Fruit ■ of 



Celandine (Chtilidonium majus), with the valves separating from the 

 placentas. 



Gentian {fig. 522), in which case the dehiscence takes the 

 septioidal form, and each valve therefore represents one of 

 the component carpels of the fruit ; or the dehiscence may take 

 place through the dorsal sutures, as in the Heartsease (fig. 515), 

 in which case it takes the locuUcidal form of dehiscence, and each 

 valve is composed of the adjoining halves of two carpels. These 

 forms may be readily distinguished by the varying attachment 

 of the placentas and seeds in the two cases ; thus, in the former 



