= Disc floret
A <disc floret> is a small tubular <flower> within a <flower head> of <Asteraceae>. Its <corolla> usually ends in approximately equal lobes. In a radiating daisy-like head, <disc florets> occupy the central region, surrounded by <ray florets>; other heads can contain only tubular <flowers>. The word disc describes the collective arrangement, not a flat disc-shaped individual <flower>.<Asteraceae in the New South Wales Flora Online>[Description: corolla forms and combinations within a head]{ref}
A hand-lens comparison makes the unit clear. Lift one central <disc floret> from a <common daisy> head and follow its narrow <corolla> down toward the <ovary (botany)>. Then compare an outer <ray floret> with its extended strap-like <corolla>. Both are whole <flowers>, even though the outer one resembles a single <petal> of a larger blossom.
An illustrative count of twenty central <disc florets> and ten peripheral <ray florets> describes thirty constituent <flowers>, not thirty <petals> of one <flower>. Whether each unit is fertile must be checked from its reproductive structures and the <species>, rather than inferred just from its position.
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