diff --git a/src/hack.c b/src/hack.c
index df437391a..c94363d91 100644
--- a/src/hack.c
+++ b/src/hack.c
@@ -1363,7 +1363,7 @@ domove()
 
         if (boulder)
             Strcpy(buf, ansimpleoname(boulder));
-        else if (solid)
+        else if (solid && glyph_is_cmap(glyph))
             Strcpy(buf, the(defsyms[glyph_to_cmap(glyph)].explanation));
         else if (!Underwater)
             Strcpy(buf, "thin air");
diff --git a/src/pager.c b/src/pager.c
index 280cf0a05..e8d7c168b 100644
--- a/src/pager.c
+++ b/src/pager.c
@@ -273,7 +273,8 @@ lookat(x, y, buf, monbuf)
 	Strcpy(buf, Is_airlevel(&u.uz) ? "cloudy area" : "fog/vapor cloud");
 	break;
     default:
-	Strcpy(buf,defsyms[glyph_to_cmap(glyph)].explanation);
+	if (glyph_is_cmap(glyph))
+	    Strcpy(buf,defsyms[glyph_to_cmap(glyph)].explanation);
 	break;
     }