; 94 Principles of Plant Culture. 



of these parts is of great importance to the botanist in 

 determining species, and also to the plant breeder who 

 would practice cross-pollination (152, 440), hence we 

 need to consider them in detail. The cherry blossom, 

 of which a vertical section appears in Fig. 45, will serve 

 as our first example. 



142. The Calyx (ca'-lyx). Beginning at the bottom, 

 the part marked C in the figure, is called the calyx. This 

 is green in the normal cherry flower. In some plants, 

 as the flax, the calyx is composed of several distinct, 



more or less leaf- 

 like parts, each of 

 which is called a 

 sepal (se'pal). I n 

 the cherry blossom, 

 the sepals are 

 united nearly to the 

 top. The calyx is 



FIG. 45. Section of cherry blossom. C calyx; Usually green, but 

 Cor. corolla; S stamens. j n the tulip and 



some other flowers it is of another color. In the apple 

 and pear, the calyx becomes a part of the fruit, and its 

 'points are visible in the depression opposite the stem. 



143. The Corolla (co-rol'-la). The more spreading part 

 : of the cherry blossom, which is normally white (Cor. r 

 Fig. 45) constitutes the corolla. In the cherry, the 

 corolla consists of fiVe distinct parts, only three of which 

 appear in the figure, called petals (pet'-als). In many 

 plants, as the pumpkin and morning glory, the petals are 

 united. In other plants they are united a part of the 

 way to the top. The corolla is usually of some other 

 color than green. 



