diff --git a/Geo/MRep.h b/Geo/MRep.h
index 24bfcef29a318869885bb501f583163a6f889da7..853b427e3d53e944fc2b749cf254aa7c144bc529 100644
--- a/Geo/MRep.h
+++ b/Geo/MRep.h
@@ -33,6 +33,7 @@
 #include "Message.h"
 #include "OS.h"
 
+// A mesh representation.
 class MRep {
  protected:
   // container for the edge representation