diff --git a/lib/ransack/adapters/active_record/ransack/constants.rb b/lib/ransack/adapters/active_record/ransack/constants.rb
index bc5ce1a..41e4ae2 100644
--- a/lib/ransack/adapters/active_record/ransack/constants.rb
+++ b/lib/ransack/adapters/active_record/ransack/constants.rb
@@ -8,21 +8,11 @@ module Ransack
         :formatter => proc { |v| "%#{escape_wildcards(v)}%" }
         }
       ],
-      ['i_cont'.freeze, {
-        :arel_predicate => 'i_matches'.freeze,
-        :formatter => proc { |v| "%#{escape_wildcards(v)}%" }
-      }
-      ],
       ['not_cont'.freeze, {
         :arel_predicate => 'does_not_match'.freeze,
         :formatter => proc { |v| "%#{escape_wildcards(v)}%" }
         }
       ],
-      ['i_not_cont'.freeze, {
-        :arel_predicate => 'i_does_not_match'.freeze,
-        :formatter => proc { |v| "%#{escape_wildcards(v)}%" }
-      }
-      ],
       ['start'.freeze, {
         :arel_predicate => 'matches'.freeze,
         :formatter => proc { |v| "#{escape_wildcards(v)}%" }