diff --git a/skimage/io/_plugins/pil_plugin.py b/skimage/io/_plugins/pil_plugin.py
index 7ff2e191..ae74ff7b 100644
--- a/skimage/io/_plugins/pil_plugin.py
+++ b/skimage/io/_plugins/pil_plugin.py
@@ -176,20 +176,23 @@ def ndarray_to_pil(arr, format_str=None):
         mode = 'L'
         mode_base = 'L'
 
+    try:
+        array_buffer = arr.tobytes()
+    except AttributeError:
+        array_buffer = arr.tostring()  # Numpy < 1.9
+
     if arr.ndim == 2:
         im = Image.new(mode_base, arr.T.shape)
         try:
-            im.frombytes(arr.tobytes(), 'raw', mode)
+            im.frombytes(array_buffer, 'raw', mode)
         except AttributeError:
-            im.fromstring(arr.tostring(), 'raw', mode)
-
+            im.fromstring(array_buffer, 'raw', mode)  # PIL 1.1.7
     else:
+        image_shape = (arr.shape[1], arr.shape[0])
         try:
-            im = Image.frombytes(mode, (arr.shape[1], arr.shape[0]),
-                                 arr.tobytes())
+            im = Image.frombytes(mode, image_shape, array_buffer)
         except AttributeError:
-            im = Image.fromstring(mode, (arr.shape[1], arr.shape[0]),
-                                  arr.tostring())
+            im = Image.fromstring(mode, image_shape, array_buffer)  # PIL 1.1.7
     return im