  We present in-plane infrared reflectance measurement on two superconducting
cuprates with relatively low T$_c$: a nearly optimally-doped
Bi$_2$Sr$_{1.6}$La$_{0.4}$CuO$_{6+\delta}$ with T$_c$=33 K and an underdoped
La$_{1.89}$Sr$_{0.11}$CuO$_4$ with T$_c$=30 K. The measurement clearly reveals
that the superconducting energy gap is distinct from the pseudogap. They have
different energy scales and appear at different temperatures. The results
suggest that the pseudogap is not a precursor to the superconducting state. The
data also challenge the longstanding viewpoint that the superconductivity
within the ab-plane is in the clean limit and the superconducting pairing
energy gap could not be detected by in-plane infrared spectroscopy.
