diff --git a/src/ciderlib/twod/twocont.c b/src/ciderlib/twod/twocont.c
index 5b2e93a77..590dffe27 100644
--- a/src/ciderlib/twod/twocont.c
+++ b/src/ciderlib/twod/twocont.c
@@ -253,7 +253,7 @@ void
 	      pNode->fPPsiOx   = spGetElement( matrix, pEqn, psiEqnOxP );
 	    }
 	  } else { /* Horizontal Slice */
-	    if ( nIndex <= 1 ) { /* Top Side */
+	    if ( nIndex == 0 || nIndex == 3 ) { /* Left (Top?) Side : bug 483 */
 	      pNode->fNPsiIn   = spGetElement( matrix, nEqn, psiEqnInM );
 	      pNode->fNPsiInP1 = spGetElement( matrix, nEqn, psiEqnInP );
 	      pNode->fNPsiOx   = spGetElement( matrix, nEqn, psiEqnOxM );
diff --git a/src/ciderlib/twod/twoncont.c b/src/ciderlib/twod/twoncont.c
index 6eb832c56..d491e99cc 100644
--- a/src/ciderlib/twod/twoncont.c
+++ b/src/ciderlib/twod/twoncont.c
@@ -211,7 +211,7 @@ void
 	      pNode->fNPsiOx   = spGetElement( matrix, nEqn, psiEqnOxP );
 	    }
 	  } else { /* Horizontal Slice */
-	    if ( nIndex <= 1 ) { /* Top Side */
+	    if ( nIndex == 0 || nIndex == 3 ) { /* Left (Top?) Side : bug 483 */
 	      pNode->fNPsiIn   = spGetElement( matrix, nEqn, psiEqnInM );
 	      pNode->fNPsiInP1 = spGetElement( matrix, nEqn, psiEqnInP );
 	      pNode->fNPsiOx   = spGetElement( matrix, nEqn, psiEqnOxM );
diff --git a/src/ciderlib/twod/twopcont.c b/src/ciderlib/twod/twopcont.c
index 67e3bc22f..6b2b81feb 100644
--- a/src/ciderlib/twod/twopcont.c
+++ b/src/ciderlib/twod/twopcont.c
@@ -210,7 +210,7 @@ void
 	      pNode->fPPsiOx   = spGetElement( matrix, pEqn, psiEqnOxP );
 	    }
 	  } else { /* Horizontal Slice */
-	    if ( nIndex <= 1 ) { /* Top Side */
+	    if ( nIndex == 0 || nIndex == 3 ) { /* Left (Top?) Side : bug 483 */
 	      pNode->fPPsiIn   = spGetElement( matrix, pEqn, psiEqnInM );
 	      pNode->fPPsiInP1 = spGetElement( matrix, pEqn, psiEqnInP );
 	      pNode->fPPsiOx   = spGetElement( matrix, pEqn, psiEqnOxM );