ITS KINDS. 327 



rate from each other, or from a slender central axis, called the Car- 

 pophore ; as in all Umbelliferous plants (Fig. 735-737), to which, 

 indeed, the name is restricted. Each separate carpel, or half- 

 fruit, is termed a HEMICARP, or MERICARP, and its inner face 

 the Commissure. 



607. A Caryopsis is a thin and membranaceous pericarp, like an 

 achenium, but adherent to the surface of the seed, so as to be in- 

 separable from its proper covering. The grains of Wheat, Maize, 

 and most Grasses, are examples (Fig. 463-465). 



608. A Utricle is a caryopsis which does not adhere to the seed ; 

 or it is an achenium or other one-celled and one-seeded fruit, with 

 a thin and membranous loose pericarp, as in Chenopodium and 

 Amarantus. 



609. A Nut is a hard one-celled and one-seeded indehiscent fruit, 

 like an achenium, but usually produced from an ovary of two or 

 more cells with one or more ovules in each, all but a single ovule 

 and cell having disappeared during its growth (585) ; as in the 

 Hazel, Beech, Oak (Fig. 1044), Chestnut, Cocoa-nut, &c. The 

 nut is often inclosed or surrounded by a kind of involucre (393), 

 termed a Cupule ; as the cup at the base of the acorn, or the burr 

 of the chestnut. 



610. A Samara is a name applied to a nut, or achenium, having a 

 winged apex or margin; as in the Birch and Elm (Fig. 1014). 

 The fruit of the Maple consists of two united samarae (Fig. 653). 



611. A Berry is an indehiscent fruit which is fleshy or pulpy 

 throughout; as the grape, gooseberry (Fig. 707), and persimmon 

 (Fig. 818). The orange, sometimes termed a HESPERIDIUM, is 

 merely a berry with a leathery rind. 



612. A Pome, such as the apple, pear, and quince, (Fig. 685- 

 688,) is a fruit composed of two or more papery, cartilaginous, or 

 bony carpels, usually more or less involved in a pulpy expansion of 

 the receptacle or disk, and the whole invested by the thickened and 

 succulent tube of the calyx. It may be readily understood by com- 

 paring a rose-hip with a haw, a quince, or an apple. 



613. A Pepo is an indehiscent fleshy, or internally pulpy fruit, 

 composed usually of three carpels, invested by the calyx, and with 

 a firm rind ; as the cucumber, melon, and gourd. Its proper 

 structure, which has been variously misconceived, may readily be 

 gathered from a cross-section of a very young melon or gourd 

 (Fig. 449). The three large placenta project from the axis to the 



