diff --git a/skimage/morphology/tests/test_convex_hull.py b/skimage/morphology/tests/test_convex_hull.py
index ad7f57a7..67850cf2 100644
--- a/skimage/morphology/tests/test_convex_hull.py
+++ b/skimage/morphology/tests/test_convex_hull.py
@@ -46,7 +46,7 @@ def test_qhull_offset_example():
        151, 152, 153, 154, 147, 148, 149, 150, 151, 152, 153, 148, 149,
        150, 151, 152, 149, 150, 151, 150]))
     image = np.zeros((1392, 1040), dtype=bool)
-    image[ nonzeros ] = True
+    image[nonzeros] = True
     expected = image.copy()
     assert_array_equal(convex_hull_image(image), expected)