Index: kernel/include/IMP/internal/AttributeTable.h
===================================================================
--- kernel/include/IMP/internal/AttributeTable.h	(revision 393)
+++ kernel/include/IMP/internal/AttributeTable.h	(working copy)
@@ -85,6 +85,7 @@
   for (unsigned int i=0; i< map_.size(); ++i) {
     if (map_[i] != Value()) {
       out << prefix;
+      out << Key(i).get_string() << ": ";
       if (md != NULL) {
         out << md->get_value(map_[i]);
       }