LESSON 20.] 



MULTIPLE FRUITS. 



133 



361. The Silique (Fig. 310), the peculiar pod of the Mustard fam- 

 ily ; which is two-celled by a false partition stretched across between 

 two parietal placentae. It generally opens by two valves 



from below upwards, and the placentae with the partition 

 are left behind when the valves fall off. 



362. A Silide OF Pouch is only a short and broad silique, 

 like that of the Shepherd's Purse, of the Candy-tuft, &c. 



363. The Pyxis is a pod which opens by a circular hori- 



zontal line, the upper part forming a lid, as 

 in Purslane (Fig. 311), the Plantain, Hen- 

 bane, &c. In these the dehiscence extends 

 all round, or is circumcissile. So it does 

 in Fig. 298, which represents a sort of one- 

 seeded pyxis. In Jeffersonia or Twin-leaf, the line 

 does not separate quite round, but leaves a portion 

 to form a hinge to the lid. 



364. Multiple OF Collective Fruits (334) are, properly speaking, 

 masses of fruits, resulting from several or many blossoms, aggre- 

 gated into one body. The pine-apple, mulberry, Osage-orange, and 

 the fig, are fruits of this kind. This latter is a peculiar form, how- 

 ever, being to a mulberry nearly what a Rose-hip is to a strawberry 

 (Fig. 279, 280), namely, with a hollow receptacle bearing the flowers 

 concealed inside ; and the whole eatable part is this pulpy common 

 receptacle, or hollow thickened flower-stalk. 



365. A Strobile, or Cone (Fig. 314), is the pe- 

 culiar multiple fruit of Pines, Cypresses, and 

 the like ; hence named Coniferce, viz. cone- 

 bearing plants. As already shown (322), these 

 cones are made of open pistils, mostly in the 

 form of flat scales, regularly overlying each 

 other, and pressed together in a spike or head. 



Each scale bears one or two naked seeds on its inner face. When 

 the cone is ripe and dry, the scales turn back or diverge, and the 

 seed peels off and falls, generally carrying with it a wing, which was 

 a part of the lining of the scale, and which facilitates the dispersion 

 of the seeds by the wind (Fig. 312, 313). In Arbor- Vitae, the scales 



FIG. 310. Silique of Spring Cress (Cardamine rhomboidea), opening. 

 FIG. 311. The pyxis, or pod, of the common Purslane 



FIG. 312. Inside view of a scale from the cone of Pitch-Pine ; with one of the seeda 

 (Fig. 313) detached ; the other in its place on the scale. 



12 



