THE CASTOR BEAN 



lid 



The Calyx composed of Sepals. The lower row, which is 

 on the outer side of the flower, is made up of small parts which 

 are usually green and leaf-like in appearance. This row is 

 known as the calyx, and the leaves of which it is composed 

 are called sepals. 



The Corolla composed of Petals. Just above and within 

 the calyx, in an ordinary flower, is a second row of leaves, 

 usually larger than the calyx and of some brilliant color. This 

 row of leaves is known as the corolla and the individual 

 leaves as petals, pi. It is these colored 

 petals that give the flower its brilliancy, 

 and their function seems to be to attract 

 the insects, that are useful to the flower 

 in producing cross fertilization; see page 

 267. The calyx and corolla together are 

 sometimes known as the perianth (Gr. peri 

 = around -f anthos = flower). In some 

 flowers either the calyx or the corolla may 

 be lacking, and in others both may be lack- 

 ing. When only a single row of leaves is 

 found in the perianth, it is customary to call 

 it a calyx, irrespective of its shape and color, 

 and such plants are usually spoken of as apeta- 

 lous (Gr. a = without + petalon = a leaf). 



The Stamens. Within the petals is a FIG. 61. THREE 

 third row of leaves, the stamens, st, which, 

 however, have almost wholly lost their re- 

 semblance to leaves. Each of these consists 

 of a delicate stem, called the filament (Fig. 

 61), at the top of which are little sacs, usu- of splitting open to dia, 

 ally two in number, which are known as the 

 anther, a. Within these sacs are. produced large numbers 

 of spores, the spores in this case being called pollen; Fig. 62. 

 The stamens are usually as many as the petals, although in 

 some flowers there are two or three times as many, and in 



STAMENS WITH 

 D I F F ERE NT 

 FORMS OF AN- 

 THERS 



a, showing methods 

 splitting open tc 

 charge the pollen. 



