THE FLOWER 35 
These are not necessarily both present in the same flower, 
although they often are. In the hazel the stamens are alone 
present in the catkin flowers (lambs’-tails), whilst the carpels 
are in other flowers on the same branch (Plate IIL, — 
Fig. 58). 
Some plants have flowers which bear only stamens, the 
carpels being not only in a separate flower, but on a different 
plant, as in the willow (Plate IIL, Figs. 55, 56). 
The stamens together form the andrecium, the carpels the 
gynecium, or pistil. The | 
stamens produce pollen and 
the carpels bear little, white 
bodies, the ovules, which 
eventually form seeds. The 
only parts of a flower essen- 
tial for the production of 
fruit and seed are the stamens 
and carpels. 
The A comparison of 
Calyx. different . flowers, 
such as the buttercup, violet, 
larkspur, marsh  marigold, 

Fic. 35.—TRANSVERSE SECTION OF 
Bup or Tutip. 
sweet pea, shows that the  &, calyx; ¢, corolla; a, anthers ; 
calyx and corolla are of very %” &2#c1u™ 
great variéty. The calyx is usually green. Sometimes, as in 
_ the primrose, the sepals are joined to each other, forming a 
tube; very often, as in the buttercup and wallflower, they are 
free. Asarule, the sepals are small and insignificant com- 
pared with the petals; but sometimes they are the most 
conspicuous part of the flower, asin the marsh marigold, globe 
flower, Christmas rose, larkspur. In these the corolla is either 
absent or very much reduced, and the calyx performs some of 
the work of the corolla; it attracts insects. Again, in many 
flower-heads, composed of a number of little flowers, as the 
dandelion, the sepals are merely hairs which serve as organs of 
dispersion for the fruit, the flowers being protected, not by 
the calyx, but by the involucre of bracts (Plate V., Fig. 89). 
3—2? 
