DEHISCENT SYNCAKPOUS FRUITS. 265 



the stone of the fruit). In Cornus mas (fig. 473), there are two stony 

 cells, n, surrounded by the fleshy epicarp and mesocarp, and as they 

 are close together, and one is often abortive 

 (fig. 473, 2, I), there is a direct transition 

 to the Drupe. 



554. Dehiscent Syncarpons Fruits. 



The Capsule (capsula, a little chest). This 

 name is applied generally to all dry syn- 

 carpous fruits, which open by valves or 

 pores. The valvular capsule is observed in 

 Digitalis (fig. 445), Hibiscus esculentus (fig. 449), Cedrela angustifolia 

 (fig. 450), Mahogany (fig. 451), and Cerastium viscosum (fig. 444). 

 The porous capsule is seen in the Poppy, Antirrhinum majus (fig. 462), 

 and Campanula persicifolia (fig. 461). Sometimes the capsule opens 

 by a lid, or by circumscissile dehiscence, and it is then called a 

 Pyxidium (pyxis, a box), as in AnagaUis arvensis (fig, 458), Henbane 

 (fig. 459), and Lecythis. The capsule assumes a spiral form in the 

 Helicteres and a star-like or stellate form in Illicium anisatum. In 

 certain instances, the cells of the capsule separate from each other, and 

 open with elasticity to scatter the seeds. This kind of capsule is met 

 with in Hura crepitans, and other Euphorbiacea;, where the cocci, con- 

 taining each a single seed, burst asunder with force (fig. 453); and in 

 Geraniacea?, where the cocci containing more than one seed,* separate 

 from the carpophore, and. become curved upwards by their adherent 

 styles (fig. 455). In the former case, the fruit collectively has been 

 called JKegma (ptj-yftu, a rupture). 



555. The Siliqua (siliqua, a husk or pod) (fig. 456), may be con- 

 sidered as a variety of the capsule, opening by two valves ; these are 

 detached from below upwards, close to the sutures, bearing thin parie- 

 tal placentas, which are united together by a prolongation called a 

 replum, or spurious dissepiment, dividing the fruit into two. The 

 seeds are attached on either side of the replum, either in one row 

 or in two. When the fruit is long and narrow, it is called Siliqua; 

 when broad and short, it is called Silicula. It occurs in cruciferous 

 plants, as Wallflower, Cabbages, Cresses, &c. The siliqua may be 

 considered as formed of two carpels, and two parietal placentas united 

 together so as to form a two- celled seed-vessel. Some say that in its 

 normal state it consists of four carpels, and that two of these are abor- 

 tive. There are four bundles of vessels in it, one corresponding to 

 each valve, which may be called valvular or pericarpial, and others 

 running along the edge called placental. The replum consists of two 



Fig. 473. Cruit of Cornus mas, common Cornel. 1. Transverse section detaching the tipper 

 half of the fleshy portion, s, so as to show the central kernel, n. 2. Transverse section of the 

 fruit through the central portion, n, showing that it consisted of two loculaments. I, One of the 

 loculaments empty, the other containing a seed, g. 



* The individual cocci of Geraniaceoe contain only one seed each. 



