diff --git a/puzzles.but b/puzzles.but
index 260ebbb..a48856a 100644
--- a/puzzles.but
+++ b/puzzles.but
@@ -1923,7 +1923,7 @@ You are given a map consisting of a number of regions. Your task is
 to colour each region with one of four colours, in such a way that
 no two regions sharing a boundary have the same colour. You are
 provided with some regions already coloured, sufficient to make the
-remainder of the solution unique.
+remainder of the solution unique, and these cannot be changed.
 
 Only regions which share a length of border are required to be
 different colours. Two regions which meet at only one \e{point}