  We present new results on production of 3He and t obtained by the NA49
experiment in 20A, 30A, 40A and 80A GeV central Pb+Pb collisions at the CERN
SPS. Transverse mass spectra and rapidity distributions for clusters measured
over a large phase space domain are discussed. We observe a weak dependence of
the mid-rapidity t/3He ratio on collision energy at SPS. The energy dependence
of the total yield for 3He is remarkably reproduced by a statistical hadron gas
model. A gradual decrease of the coalescence parameter B3 for 3He with $\sqrt
{s_{NN}}$ is observed.In addition, a measurement of the yield of anti-deuterons
in Pb+Pb reactions at SPS's top energy of $\sqrt {s_{NN}}$ = 17.2 GeV is
presented.
