SEED-BEARING PLANTS 
463 
of two or more petals become wholly or partly fused or 
coalesced, thus reducing the number of separate members 
of the corolla (Fig. 346). Sometimes coalescence and 
petalody of stamens will occur in the same specimen, so 
that a flower that would normally have five petals may 
have six or eight, or more, some of which have coalesced, 
as is indicated by the two or more points at the tip. 
FIG. 346. Rue anemone (Anemonella thalictroides) . i, normal flower 
with 5 petals; 3, petalody of stamens; 4, coalescence of petals (c 1 ); 2, coales- 
cence (c), and petalody of stamens. At 2, s is shown a stamen partially 
transformed into a petal, but with a portion of the anther still remaining. 
412. Mustard Family (Cruciferse). The flowers of 
the mustard family are mostly characterized by having 
the four narrow petals opening out at an angle of 90 
from each other, forming a Greek cross (Fig. 347), whence 
the family name, Cruciferae. This character of the corolla 
also appears in rare instances in other families (e.g., some 
Rubiaceae), whose corolla is then said to be "cruciferous." 
The fruit, a silique, is also one of the ear-marks of the 
