314 



THE FRUIT. 



ent style usually remains on the fruit as a long tail), and the minute 

 grains of the strawberry (Fig. 559). But it may be extended, as 

 is now generally done, to all such one-celled seed-lilie fruits result- 

 ing from a compound ovary, and even when invested with an adnate 

 calyx-tube. Of this kind is the fruit of all Compositce (Fig. 568 - 

 573). Here the tube of the calyx is incorporated with the surface 

 of the ovary, and its limb or border, obsolete in some cases (Fig. 

 568), in others appears as a crown (Fig. 569), cup, a set of teeth 

 or of scales (Fig. 570, 571), or as a tuft of bristles or hairs (Fig. 

 572, 573), &c., called the pappus. In the Lettuce and Dandelion 

 (Fig. 573), tlie achenium is rostrate, i. e. its summit is extended 

 into a slender beak. 



603. A Utricle is the same as an achenium, only with a thin and 

 BJ4 bladdery loose pericarp, like that of Goosefoot and 



Amaranth (Fig. 574, 575). The thin coat commonly 

 bursts irregularly, discharging the seed. In the true 

 Amaranths it opens by a circular line, and the upper 

 part falls as a lid, converting the fruit into a small 

 pyxis (619). 



604. A Caryopsis or Grain differs from the last in hav- 

 ing the seed completely filling the cell, and its coat 

 firmly consolidated throughout witli the very thin peri- 

 carp, as in wheat, Indian corn, and other cereal grains 

 (Fig. 622-624). Of all fruits this is tlie kind most 

 likely to be mistaken for a seed. 



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

 like an achenium, but larger, and 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 (586) ; as in the 

 Hazel, Beech, Oali (Fig. 576, 1166), Chestnut, 

 Cocoa-nut, &c. The nut is often enclosed or sur- 

 rounded by a kind of involucre, termed a Cupule ; 

 as the cup at the base of the acorn, the bur of the 

 chestnut, and the leaf-like covering of the hazel-nut. ^™ 



606. A Samara or Key-fruit is a name applied to a nut, or achenium, 

 having a winged apex or margin ; as in the Birch, Elm (P'ig. 578), 



FIG. 574. Utricle of Chenopodium album, or common Goosefoot. 575. Utricle, or pyxis, 

 of an Amaranth 

 FIG. 576. Acorn (nut) of White Oak, with its cup or cupule. 



