Roundel Heart Cherry is an old variety that was grown much in Kent. Produces heart-shaped fruits that ripen around mid July and are dark red. Soft, sweet flesh and flavoursome. It is not self fertile but can be pollinated by self fertile cherries or Waterloo.
I am not sure about the flesh colour of Roundel Heart Cherry but there are a few cherries named ‘…. Heart’. One called ‘White Heart’ or ‘Amber Heart’ has white coloured flesh. In France Biggareau cherries were bred and thery seem to have pale flesh – white or yellow also.