Hydrangeaceae

Hydrangeaceae is a family of flowering plants in the order Cornales, with a wide distribution in Asia and North America, and locally in southeastern Europe. it comprises nine (or fewer) genera with 223 known species.

In its broad sense (as treated by the Angiosperm Phylogeny Group), the family includes 17 genera, but some botanists divide the family into two, with seven genera split off into a separate family, Philadelphaceae.

The genera are characterised by leaves in opposite pairs (rarely whorled or alternate), and regular, bisexual flowers with 4 (rarely 5–12) petals. The fruit is a capsule or berry containing several seeds, the seeds with a fleshy endosperm.

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