i8 4 



BOTANY FOR BEGINNERS 



CHAP. 



lobes may be shaped like the tips of the leaves, (p. 44), and the 

 same terms are used as in describing leaves. 



The colour of the calyx and whether it is hairy or smooth, 

 must be recorded. If the calyx is coloured it is said to be 

 petaloid) as in the Christmas Rose and Anemone. In most cases 

 it is green. 



The function of the calyx is to protect the stamens and pistil 

 from injury. In those cases where it is coloured it serves to 

 attract insects. It may persist after those functions are per- 

 formed, as in the Dandelion, where it persists as a pappus 

 (Fig. 197) of hairs which aids in the 

 distribution of the seeds by the action of 

 the wind. In the Poppy the sepals fall 

 off when the flower opens. The calyx 

 may take part in forming the fruit, as in 

 the Apple and Pear. 



Corolla. If the petals are united, as 

 in the Primrose, a gamopetalons corolla 

 is formed. In its simplest form the 

 corolla consists of a number of separated 

 petals, and it is polypetalous, as in the 

 Buttercup, Wallflower, and Stitchwort. 



When the corolla springs from beneath 

 the pistil and from the thalamus, as 

 the receptacle is sometimes called, 

 in the Wallflower, Rock Cress, and 



FIG. 197. Pappus of 

 Dandelion. 



it is hypogynous^ as 

 Poppy. 



If the petals are fixed on the calyx the corolla is perigynous, 

 as in the Pea, Rose and Apple. 



[If the flower has the corolla and stamens hypogynous, it is a 

 hypogynous flower ; if the corolla and stamens are perigynous, 

 it is a perigynous flower ; and when both corolla and stamens are 

 inserted on the ovary it is an epigynous flower.] 



The corolla may spring from the top of the ovary, when it is 

 said to be epigynous, as in the Cow-Parsnip and Sea Holly. 



The number of the petals or the lobes of the corolla, the shape 

 of the petals, or the lobes, must be observed and the terms used 

 for the calyx may be employed to describe them. 



Androecium. The whole collection of stamens of a flower 

 constitute the androecium. In describing the stamens the union 



