We measured the fusion-fission excitation functions for the S-32+Ta-18
1 reaction and the S-38+Ta-181 reaction. (The radioactive S-38 beam wa
s produced by projectile fragmentation.) The thresholds were measured
to be 137.5+/-1.0 and 130.7+/-2.0 MeV for the S-32 and S-38-induced re
actions, respectively. This result agrees with the systematics of fusi
on excitation functions and may be significant in the synthesis of new
heavy nuclei.