
    No. 91-1328.
    No. 91-1546.
    City of Chicago et al. v. Environmental Defense Fund et al. Slagle v. Terrazas et al.
   C. A. 7th Cir.; and

Appeal from D. C. W. D. Tex. The Solicitor General is invited to file briefs in these cases expressing the views of the United States.  