274 A TEXTBOOK OF GENERAL BOTANY 
Composition of fruits. Some fruits are produced by superior 
ovaries, and others by inferior ones. An ovary is said to be supe- 
rior when the point of attachment of 
the calyx and corolla is below the 
ovary (Figs. 202, 203), and infe- 
rior when the point of attachment is 
above the ovary (Figs. 208, 221). 
In the latter case the torus may 
be considered as having a_bottle- 
like form, at the summit of which 
the calyx, corolla, and stamens are 
attached. In such cases the torus 
takes part in the formation of the 
fruit. When the fruit is derived from 
Note remains of calyx at base of ; : 
fruit. (x 2) a superior ovary, the remains of the 
calyx can frequently be found at the 
base of the fruit, as in the grapefruit (Fig. 251). When the ovary 
is inferior, the remains of the calyx can sometimes be plainly seen 

Fig.251. Grapefruit developed 
from superior ovary 

Fic. 255. Cross section of an 
) a apple fruit, showing ripened 
Fig. 252. Berry of guava developed from — ovarysurrounded byenlarged 
an inferior ovary. (X 4) torus. (x 3) 



at the apex of the fruit (Fig. 252). In the flower of the apple 
there are five imperfectly fused carpels which are more or less 
