One natural question of lattice
theory has been (i) whether there exists an equational class of lattices which cannot
be characterized by any finite list of lattice identities. Another question, due to B.
Jónsson, is (ii) whether there exists an equational class of lattices which
is not determined by its finite members. We shall show that the answers
to both questions are affirmative, even with the additional requirement of
modularity. The examples are constructed from lattices corresponding to projective
planes.