bright as X) that we did not detect, and that could not have been missed by our observations (see Figure 8, dotted contour). In the second case, the redshift of X is not likely to exceed that of G significantly, because the Einstein ring radius $\theta_E({\rm X})$ for X depends strongly on $z_{\rm X}$. We can illustrate this property by assuming that the mass distribution of G is a singular isothermal sphere, an approximation that preserves the characteristic angular scale of the lens system. For such a distribution, the radius of the multiple-image region for a source at $z_{\rm X}$ is $2 \,\theta_E({\rm X})$. Within this approximation, for X to be a single image, $\theta_E({\rm X}) < \theta({\rm X})/2$, where $\theta({\rm X}) \sim 1\farcs5$ is the angular distance from X to the center of brightness of G (Tables 1 and 2). However, from Table 4, $\theta_E \sim 1\farcs2 \approx \theta({\rm X})$; which is approximately equivalent to $\theta_E({\rm X}) {\mathrel{\raise.3ex\hbox{$<$}\mkern-14mu\lower0.6ex\hbox{$\sim$}}}\theta_E/2$. Thus, if $z_{\rm G} \approx 1$, then $z_{\rm X}-z_{\rm G} \approx0.4$, with this difference being smaller for any other $z_{\rm G}$. In the third case, we assumed that the M/L$_I$ ratio of X is equal to that of G, and fitted 