diff --git a/src/openflexure_microscope_server/stitching.py b/src/openflexure_microscope_server/stitching.py
index c9a9e460..b88c4036 100644
--- a/src/openflexure_microscope_server/stitching.py
+++ b/src/openflexure_microscope_server/stitching.py
@@ -47,7 +47,7 @@ class BaseStitcher:
     """A base stitching class for all stitchers. Don't initialise this directly.
 
     The base class has no way to run the command. Child classes should either implement
-    a ``start``, ``running``, and ``wait`` methods if return after starting the
+    ``start``, ``running``, and ``wait`` methods if return after starting the
     subprocess and can be polled or waited on like a thread; or ``run`` if the
     the function blocks while the stitching subprocess is ongoing and return once
     complete.
@@ -207,7 +207,7 @@ class FinalStitcher(BaseStitcher):
         self._mode = "all"
 
         tiff_arg = "--stitch_tiff" if stitch_tiff else "--no-stitch_tiff"
-        self._extra_args = ["--stitch-dzi", tiff_arg]
+        self._extra_args = ["--stitch_dzi", tiff_arg]
 
     def _process_inputs(
         self,
diff --git a/tests/test_stitching.py b/tests/test_stitching.py
index ae2e2abd..ef248b82 100644
--- a/tests/test_stitching.py
+++ b/tests/test_stitching.py
@@ -76,7 +76,7 @@ FINAL_EXPECTED_COMMAND = [
     "openflexure-stitch",
     "--stitching_mode",
     "all",
-    "--stitch-dzi",
+    "--stitch_dzi",
     "--no-stitch_tiff",
     "--minimum_overlap",
     "0.09",