diff --git a/Tests/test_numpy.py b/Tests/test_numpy.py
index 4f2a5afb1..3cadd4e1d 100644
--- a/Tests/test_numpy.py
+++ b/Tests/test_numpy.py
@@ -43,29 +43,40 @@ class TestNumpy(PillowTestCase):
             # print dtype, list(i.getdata())
             return i
 
-        # self.assert_image(to_image(numpy.bool, boolean=1), "1", (10, 10))
-        # self.assert_image(to_image(numpy.bool8, boolean=1), "1", (10, 10))
+        # Check supported 1-bit integer formats
+        self.assertRaises(TypeError, lambda: to_image(numpy.bool))
+        self.assertRaises(TypeError, lambda: to_image(numpy.bool8))
 
-        self.assertRaises(TypeError, lambda: to_image(numpy.uint))
+        # Check supported 8-bit integer formats
         self.assert_image(to_image(numpy.uint8), "L", (10, 10))
-        self.assertRaises(TypeError, lambda: to_image(numpy.uint16))
-        self.assertRaises(TypeError, lambda: to_image(numpy.uint32))
-        self.assertRaises(TypeError, lambda: to_image(numpy.uint64))
-
-        self.assert_image(to_image(numpy.int8), "I", (10, 10))
-        if Image._ENDIAN == '<':  # Little endian
-            self.assert_image(to_image(numpy.int16), "I;16", (10, 10))
-        else:
-            self.assert_image(to_image(numpy.int16), "I;16B", (10, 10))
-        self.assert_image(to_image(numpy.int32), "I", (10, 10))
-        self.assertRaises(TypeError, lambda: to_image(numpy.int64))
-
-        self.assert_image(to_image(numpy.float), "F", (10, 10))
-        self.assert_image(to_image(numpy.float32), "F", (10, 10))
-        self.assert_image(to_image(numpy.float64), "F", (10, 10))
-
         self.assert_image(to_image(numpy.uint8, 3), "RGB", (10, 10))
         self.assert_image(to_image(numpy.uint8, 4), "RGBA", (10, 10))
+        self.assert_image(to_image(numpy.int8), "I", (10, 10))
+
+        # Check non-fixed-size integer types
+        self.assertRaises(TypeError, lambda: to_image(numpy.uint))
+        self.assert_image(to_image(numpy.int), "I", (10, 10))
+
+        # Check 16-bit integer formats
+        if Image._ENDIAN == '<':
+            self.assert_image(to_image(numpy.uint16), "I;16L", (10, 10))
+        else:
+            self.assert_image(to_image(numpy.uint16), "I;16B", (10, 10))
+        self.assertRaises(TypeError, lambda: to_image(numpy.int16))
+
+        # Check 32-bit integer formats
+        self.assertRaises(TypeError, lambda: to_image(numpy.uint32))
+        self.assert_image(to_image(numpy.int32), "I", (10, 10))
+
+        # Check 64-bit integer formats
+        self.assertRaises(TypeError, lambda: to_image(numpy.uint64))
+        self.assertRaises(TypeError, lambda: to_image(numpy.int64))
+
+        # Check floating-point formats
+        self.assert_image(to_image(numpy.float), "F", (10, 10))
+        self.assertRaises(TypeError, lambda: to_image(numpy.float16))
+        self.assert_image(to_image(numpy.float32), "F", (10, 10))
+        self.assert_image(to_image(numpy.float64), "F", (10, 10))
 
     # based on an erring example at
     # http://stackoverflow.com/questions/10854903/what-is-causing-dimension-dependent-attributeerror-in-pil-fromarray-function