-;;;
-;;; KLUDGE: The genesis code has raw offsets of slots in this
-;;; structure hardwired into it. It would be good to rewrite that code
-;;; so that it looks up those offsets in the compiler's tables, but
-;;; for now if you change this structure, lucky you, you get to grovel
-;;; over the genesis code by hand.:-( -- WHN 19990820