12 



FOLLICLE, LEGUME, SILIQUE 



[CH. 



suture only and allowing its several seeds to escape. 

 Curiously, follicles rarely occur isolated (some species of 

 Delphinium, Connaraceae, Proteacese, &c.), but in groups 

 of three to many (ceterios) they are common in Ranun- 

 culaceae (Peony, Columbine, Larkspur, Aconitum (Fig. 7), 

 &c.), Magnoliacese (Illicium, Magnolia, &c.), CrassulaceaB 

 (Sempervivum), &c. The rule is that follicles dehisce by 

 the ventral suture, where the seeds are borne (Figs. 3 and 

 7): in Magnolia, however, they split down the dorsal 

 suture (Fig. 42). 



In Asclepiadacese, Sterculiacese and some other cases, 

 we have a syncarpous ovary separating into its constituent 

 carpels, which become follicles, as the fruit matures. 



When the fruit has the same characters as the fol- 

 licle, but splits down both sutures, it is termed a Legume 

 (Fig. 5), and this again is a common and 

 wide-spread type especially characteristic of 

 the natural order Leguminosae (Peas, Beans, 

 Vetches, &c.). 



In the Cruciferse there prevails a type of 

 fruit which at first sight looks like a pod, 

 and without examination may be confounded 

 with a Legume. It opens by two valves, 

 but leaves the placentas and seeds behind 

 attached to the two sides of a sort of frame, 

 across which a thin partition-membrane is 

 stretched. The distinctive point is that 

 each valve is the dorsal and greater portion 

 of a carpel, and the frame the united edges 

 of the two carpels, the membrane being 

 a false septum stretched between them. 

 This fruit is known as a Silique (Fig. 8). 

 The above three types of fruit agree in being dry and 

 dehiscent, and shedding the seeds from the cavity; but 



Fig. 8. Wall- 

 flower, silique 

 (Bai). 



