--- a/text/ncat.tex	Wed Mar 23 15:30:38 2011 -0700
+++ b/text/ncat.tex	Wed Mar 23 15:33:48 2011 -0700
@@ -826,8 +826,7 @@
 \rm
 \label{ex:bordism-category}
 For a $k$-ball $X$, $k<n$, define $\Bord^n(X)$ to be the set of all $k$-dimensional PL
-submanifolds $W$ of $X\times \Real^\infty$ such that $\bd W$ is 
-contained in $\bd X \times \Real^\infty$.
+submanifolds $W$ of $X\times \Real^\infty$ such that $\bd W = W \cap \bd X \times \Real^\infty$.
 For an $n$-ball $X$ define $\Bord^n(X)$ to be homeomorphism classes (rel boundary) of such $n$-dimensional submanifolds;
 we identify $W$ and $W'$ if $\bd W = \bd W'$ and there is a homeomorphism
 $W \to W'$ which restricts to the identity on the boundary.