258 



PLANT LIFE. 



grasses (fig. 282). Bractlets sometimes form a sort of second 

 calyx beneath the true calyx, as in hollyhock. In the straw- 

 berry and its kin, the somewhat similar extra whorl of leaves 



FIG. 282. 



FIG. 283. 



FIG. 284. 



FIG. 282. A single flower of wheat, showing two chaffy bracts, b, 7>, which protect it. 

 For the parts of the flower see fig. 283. Magnified about 5 diam. After Luerssen. 



FIG. 283. The flower of wheat with bracts removed, showing two fleshy bractlets, c, c, 

 the lodicules, which at time of blossoming swell and open the bracts. Three stamens, 

 and a carpel with two styles and feathery stigmas constitute the flower proper. Magni- 

 fied about 5 diam. After Luerssen. 



FIG. 284. Outline of the flower of strawberry, seen from beneath, c, corolla; k, calyx; 

 k 1 ', epicalyx, formed by the union of the stipules of the sepals. Slightly reduced. 

 After Luerssen. 



belongs to the calyx, being the stipules of the calyx leaves 

 united in the course of development (fig. 284). 



The " cup ' ' of the acorn, the "shuck ' of the beechnut, 

 and the ' ' bur ' ' of the chestnut represent late-developed out- 

 growths beneath the flower or the flower cluster, which be- 

 come scaly or spiny as the nut develops, and serve to protect 

 the forming fruits. 



360. The torus. In the vicinity of the flower leaves the 

 internodes of the stem are rarely developed, so that the nodes 

 from which the flower leaves arise are close together. More- 

 over, the axis is usually enlarged, so as to give greater space 

 for the numerous leaves. This enlarged portion is called the 

 receptacle or torus. When the leaves are removed or fall 

 naturally the torus shows ordinarily a rounded or conical sur- 

 face, with close-set scars left by their bases (fig. 285). When 



