= Asteraceae
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<Asteraceae> is a family of <angiosperms> characterized by <flowers> grouped into compact <flower heads>. The apparent single blossom of a <common daisy> is an <inflorescence>: its small constituent <flowers> are <florets>, surrounded collectively by an <involucre> of <bracts>. A <ray floret> has an extended strap-like part of the <corolla>; a <disc floret> has a tubular <corolla>. Different members of <Asteraceae> have different combinations of these forms.<Asteraceae in the New South Wales Flora Online>[Description: inflorescence and corolla types]{ref}
The <calyx> may form a <pappus> of hairs, bristles or scales, or be absent. The dry, one-seeded <fruit> is often called a <cypsela>, although some floras use <achene> more broadly. These connected characters explain why classifying the whole head as one large <flower> loses useful anatomical information.<Asteraceae in the New South Wales Flora Online>[Calyx and fruit; PlantNET uses achene broadly]{ref}
For a simple observation, examine a <common daisy> head with a hand lens. Trace an outer <ray floret> toward its base, then compare the small tubular <disc florets> in the center. The repeated floral units belong to one organized <flower head>; the surrounding <bracts> belong to the collective enclosure. Counting apparent petals around the head therefore does not count the <petals> of one <flower>.
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