diff --git a/test-runner/android/test/SingleLaunchActivityTestCase.java b/test-runner/android/test/SingleLaunchActivityTestCase.java
index 8d43b73..b63b3ce 100644
--- a/test-runner/android/test/SingleLaunchActivityTestCase.java
+++ b/test-runner/android/test/SingleLaunchActivityTestCase.java
@@ -37,7 +37,11 @@
     private static boolean sActivityLaunchedFlag = false;
 
     /**
-     * @param pkg The package of the instrumentation.
+     * <b>NOTE:</b> The parameter <i>pkg</i> must refer to the package identifier of the
+     * package hosting the activity to be launched, which is specified in the AndroidManifest.xml
+     * file.  This is not necessarily the same as the java package name.
+     *
+     * @param pkg The package hosting the activity to be launched.
      * @param activityClass The activity to test.
      */
     public SingleLaunchActivityTestCase(String pkg, Class<T> activityClass) {