May be that is why it has been named as 'heterophylla', I think.
I understand that the leaves here are variable in shape and size. But I used to get confused with the specific epithet 'heterophylla' to a different plant, E.cyathophora, which has two-colored leaf-like bracts.
Their nomenclature is still confusing!
Vijayasankar RamanNational Center for Natural Products Research
University of Mississippi