In article , Helen
writes
I don't know if this is any help but in my Dorling Kindersley book of
Trees, there is a picture of 'Crataemespilus Grandiflora'. It
possesses both type of leaves. Quote from the book:

"Leaves - Elliptic to obovate, to 7.5cm (3in) long and 5cm (2in)
across, glossy green above, turning bright orange in Autumn; on
vigorous shoots deeply lobed."

Hmm. Ovate medlar leaves and lobed hawthorn leaves. Wouldn't explain
what this bizarre tree is, but suggests that a bi-generic hybrid bearing
both types of parental leaves is possible.
--
Kay Easton

Edward's earthworm page:
http://www.scarboro.demon.co.uk/edward/index.htm