diff --git a/src/com/onarandombox/utils/PurgeWorlds.java b/src/com/onarandombox/utils/PurgeWorlds.java
index bcdfcc7b..3568047c 100644
--- a/src/com/onarandombox/utils/PurgeWorlds.java
+++ b/src/com/onarandombox/utils/PurgeWorlds.java
@@ -41,7 +41,7 @@ public class PurgeWorlds {
         }
         ArrayList<String> allMobs = new ArrayList<String>(world.getAnimalList());
         allMobs.addAll(world.getMonsterList());
-        purgeWorld(sender, world, allMobs, world.allowAnimalSpawning(), world.allowMonsterSpawning());
+        purgeWorld(sender, world, allMobs, !world.allowAnimalSpawning(), !world.allowMonsterSpawning());
     }
     
     public void purgeWorld(CommandSender sender, MVWorld mvworld, List<String> thingsToKill, boolean negateAnimals, boolean negateMonsters) {