This flower was found in Antrim Park.
It is on page 162 in Newcomb’s Wildflowers.
Common name Celandine poppy Scientific name: Stylophorum diphyllum.
Corolla: 4 separate petals.
Calyx: 2 separate petals.
Adroecium: Around 14 separate stamen. They have separate stamens but their carpels are fused.
Gynoecium type: syncarpous (and # of carpels = 4)
Flower type/ovary position: Hypogynous.
Flower symmetry: actinomorphic (regular).
Additional distinctive features: