diff --git a/lodash.js b/lodash.js
index 26c595910..919dd8e5e 100644
--- a/lodash.js
+++ b/lodash.js
@@ -5709,7 +5709,8 @@
     /**
      * This method is like `_.unzip` except that it accepts `iteratee` to specify
      * how regrouped values should be combined. The iteratee is invoked with four
-     * arguments: (accumulator, value, index, group).
+     * arguments: (accumulator, value, index, group). The first element of each
+     * group is used as the initial `accumulator` value.
      *
      * @static
      * @memberOf _
@@ -5850,7 +5851,8 @@
     /**
      * This method is like `_.zip` except that it accepts `iteratee` to specify
      * how grouped values should be combined. The iteratee is invoked with four
-     * arguments: (accumulator, value, index, group).
+     * arguments: (accumulator, value, index, group). The first element of each
+     * group is used as the initial `accumulator` value.
      *
      * @static
      * @memberOf _