diff --git a/unoptimized_lr/simple_lr_automaton.py b/unoptimized_lr/simple_lr_automaton.py
index 0dd3286d1dd74b22e63019a682fcf46546f49363..a7c1fdc1c73b70e48d6bb998d862aa855ccb8081 100644
--- a/unoptimized_lr/simple_lr_automaton.py
+++ b/unoptimized_lr/simple_lr_automaton.py
@@ -46,10 +46,10 @@ from functools import reduce
 #
 #
 # 2) Parameters based on expected use cases:
-#        * NStackItems:   Parse stack depth.
+#        * NStackDepth:   Parse stack depth.
 #        * NLongestParse: The length of the longest possible parse tree
 #
-# log_2(NStackItems)   =    WStackItems
+# log_2(NStackDepth)   =    WStackDepth
 # log_2(NLongestParse) =    WLongestParse
 #
 # In the general case, it is impossible to determine these for a given language.
@@ -133,7 +133,7 @@ from functools import reduce
 # Parse item stack:
 #
 #             (stack operation type, index for multipop, state number to push)
-#                3 bits                WStackItems        WStates
+#                3 bits                WStackDepth        WStates
 #                 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
 #                /                                           \
 #   /----------------------\                        /---------------------\
@@ -146,10 +146,13 @@ from functools import reduce
 #
 #
 # Parse index stack. Note that this is only needed if we're outputting a
-# serialized parse tree (regardless if to memory or to a stream):
+# serialized parse tree (regardless if to memory or to a stream).
+# 
+# The serialization indices can be as big as WLongestParse, and we're just storing
+# indices here, not the items.
 #
 #             (stack operation type, index for multipop, serialization index to push)
-#                3 bits                WStackItems         WLongestParse
+#                3 bits                WStackDepth         WLongestParse
 #                 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
 #                /                                           \
 #   /----------------------\                        /---------------------\