diff --git a/doc/fixes3-7-0.txt b/doc/fixes3-7-0.txt
index 2c3728764..1020dd7ed 100644
--- a/doc/fixes3-7-0.txt
+++ b/doc/fixes3-7-0.txt
@@ -1227,6 +1227,7 @@ when a werecreature in human form attacked hero, it could transform to critter
 	despite hero having the Protection_from_shape_changers_attibute
 status highlighting for hit points didn't work as intended for up or down HP
 	changes; 'up' rule was used for both, 'down' rule was ignored
+unhide an unseen water monster using a polymorph trap on land
 
 
 Fixes to 3.7.0-x General Problems Exposed Via git Repository
diff --git a/src/muse.c b/src/muse.c
index 3104bd838..d766faa88 100644
--- a/src/muse.c
+++ b/src/muse.c
@@ -2333,6 +2333,7 @@ use_misc(struct monst *mtmp)
         remove_monster(mtmp->mx, mtmp->my);
         newsym(mtmp->mx, mtmp->my);
         place_monster(mtmp, gt.trapx, gt.trapy);
+        maybe_unhide_at(gt.trapx, gt.trapy);
         if (mtmp->wormno)
             worm_move(mtmp);
         newsym(gt.trapx, gt.trapy);