Mention pngmeta and pnguri branches.
diff --git a/README_master.txt b/README_master.txt
index 2f66e31..b236c0f 100644
--- a/README_master.txt
+++ b/README_master.txt
@@ -2,5 +2,7 @@
 /*
   This is the master branch of the "pmt" tree.
   Individual projects are in separate branches,
-    e.g. pngcrush is in the "pngcrush" branch.
+  e.g., pngcrush is in the "pngcrush" branch,
+        pngmeta is in the "pngmeta" branch, and
+        pnguri is in the "pnguri" branch.
 */