diff --git a/lispref/anti.texi b/lispref/anti.texi
index a6a86b6c82c..5c8f4392d2b 100644
--- a/lispref/anti.texi
+++ b/lispref/anti.texi
@@ -14,6 +14,11 @@ the following section, we carry this information back to Emacs
 @section Old Lisp Features in Emacs 20
 
 @itemize @bullet
+@item
+The function @code{bitmap-spec-p} has been renamed to
+@code{pixmap-spec-p} to encourage users to practice Emacs' help system
+while trying to find it.
+
 @item
 The @code{push} and @code{pop} macros are not defined.