All the “composites,” or members of the sunflower family (or aster family, if you prefer) have their tiny, reduced flowers arranged in compact heads, and each head is called a “capitulum.” Before the capitulum opens, a series of bracts surrounds it, much like the sepals surround a flower bud before it opens up. When it blooms, the head will thus have this series of bracts all tucked down at the bottom, revealing the tiny flowers above.