24 The Romance of Wild Flowers 
unequally pinnate leaf because of the odd leaflet. 
Now look at the base of the leaf-stalk, and you will 
notice a pair of wings, so to speak; these are called 
stipules. This is all very tedious and uninteresting, 
no doubt, but if we wish to understand all about 
flowers, we must also know the details of structure 
of the plants that bear the flowers, and perhaps 
before we have gone very far these details may 
prove to have an interest of their own. Now let us 
look at the Dog Rose-flower. 
At the top of the flower-stalk is a smooth 
green egg-shaped knob which can be _ best 
observed in this unopened bud, of which it 
will be well to make a vertical section. It 
is known as the receptacle, and though that 
Rose-bud Strikes us aS an appropriate name looking 
at its hollowed character in the Rose, we shall 
find in other plants that it is more often flat or 
convex, sometimes indeed conical. The receptacle, 
then, is the enlarged head of the flower-stalk from 
which arise the various floral organs. 
In this Rose there grow up from the rim 
of the receptacle five rather thick green leaves 
with ragged edges, which are called sepals. 
The term is derived from a Latin word sepio, 
to hedge around or enclose, and as we see 
them in the but slightly open bud, the term 
appears very fit, for they form a hedge or By 
enclosure round the pink Rose-leaves. Col- 
lectively these sepals are called the calyx, and in 
many flowers the sepals are so closely united by 
their edges, that they can only be spoken of in 
the collective sense. Calyx means cup, and though 
