202 FOUNDATIONS OF BOTANY 
each other or distinct, or they may cohere by their fila- 
ments into a single group, when they are said to be 
Fig. 144. — Bell-Shaped 
Corolla of Bell-Flower 
(Campanula). 
monadelphous, of one brotherhood (Fig. 
151), into two groups (diadelphous) (Fig. 
152), or into many groups. In some 
flowers the stamens are held together in 
a ring by their coherent anthers (Fig. 
153). 
216. Union of Pistils.— The pistils 
may be entirely separate from each 
other, distinct and simple, as they are 
in the buttercup and the stonecrop, or 
several may join to form one compound 
pistel of more or less united carpels. In the latter case 
the union generally affects the ovaries, but often leaves 
Fic. 145.— Salver-Shaped 
Corolla of Jasmine. 
(Magnified.) 
Ovary; Placentas. 
the styles separate, or it may result 
in joining ovaries and styles, but 
leave the stigmas separate or at any 
rate lobed, so as to show of how 
many separate carpels the compound 
pistil is made up. Even when there 
is no external sign to show the 
compound nature of 
the pistil, it can usu- 
ally be recognized 
from the study of 
a cross-section of the 
Fia. 146. 
ovary. Wheel-Shaped Corolla 
217. Cells of the ft 
— Compound ovaries are very com- 
monly several-celled, that is, they consist of a number of 
