diff --git a/src/allmydata/immutable/checker.py b/src/allmydata/immutable/checker.py
index 8b734326b..3328daba3 100644
--- a/src/allmydata/immutable/checker.py
+++ b/src/allmydata/immutable/checker.py
@@ -10,8 +10,7 @@ from zope.interface import implements
 from twisted.internet import defer
 from twisted.python import log
 from allmydata import storage
-from allmydata.interfaces import IVerifierURI, \
-     ICheckerResults, IDeepCheckResults
+from allmydata.interfaces import ICheckerResults, IDeepCheckResults
 from allmydata.immutable import download
 from allmydata.util import hashutil, base32
 
diff --git a/src/allmydata/mutable/node.py b/src/allmydata/mutable/node.py
index d3c91a3b1..bb038022d 100644
--- a/src/allmydata/mutable/node.py
+++ b/src/allmydata/mutable/node.py
@@ -218,9 +218,6 @@ class MutableFileNode:
     def get_verifier(self):
         return IMutableFileURI(self._uri).get_verifier()
 
-    def get_storage_index(self):
-        return self._uri.storage_index
-
     def _do_serialized(self, cb, *args, **kwargs):
         # note: to avoid deadlock, this callable is *not* allowed to invoke
         # other serialized methods within this (or any other)
diff --git a/src/allmydata/test/common.py b/src/allmydata/test/common.py
index 5567451cc..c204bbf0d 100644
--- a/src/allmydata/test/common.py
+++ b/src/allmydata/test/common.py
@@ -120,7 +120,7 @@ class FakeMutableFileNode:
     def deep_check(self, verify=False, repair=False):
         d = self.check(verify, repair)
         def _done(r):
-            dr = DeepCheckResults(self.storage_index)
+            dr = checker.DeepCheckResults(self.storage_index)
             dr.add_check(r)
             return dr
         d.addCallback(_done)