  (Abridged) We present morphological, photometric, kinematic and line-strength
data of 48 early-type members of the rich cluster Abell 2218 at z=0.18. This
sample is both larger and spans a wider galaxy luminosity range, down to
M*_B+1, than previous studies. We compare A2218 with similar samples drawn from
local clusters to identify evolutionary changes between the samples which have
occured over the last 3Gyrs. The overall picture is one of little or no
evolution in nearly all galaxy parameters. Zeropoint offsets in the
Faber--Jackson, Mg_b-sigma and Fundamental Plane relations are all consistent
with passively evolving stellar populations. The slopes of these relations have
not changed significantly. We do however find a significant spread in the
estimated luminosity-weighted ages of the stellar populations in the galaxies,
based on line diagnostic diagrams. This age spread is seen in both the disky
early-type galaxies (S0) and also the ellipticals. We observe both ellipticals
with a strong contribution from a young stellar population and lenticulars
dominated by old stellar populations. On average, we find no evidence for
systematic differences between the populations of ellipticals and lenticulars.
This points to a common formation epoch for the bulk of the stars in most of
the early-type galaxies in A2218. This result can be reconciled with the claims
of rapid morphological evolution in distant clusters if the suggested
transformation from spirals to lenticulars does not involve significant new
star formation.
