diff --git a/include/wx/osx/bitmap.h b/include/wx/osx/bitmap.h
index 4252da9f9c..65255198e9 100644
--- a/include/wx/osx/bitmap.h
+++ b/include/wx/osx/bitmap.h
@@ -47,13 +47,8 @@ public:
     // Construct a mask from a mono bitmap (black meaning show pixels, white meaning transparent)
     wxMask(const wxBitmap& bitmap);
 
-    // implementation helper only : construct a mask from a 32 bit memory buffer
-    wxMask(const wxMemoryBuffer& buf, int width , int height , int bytesPerRow ) ;
-
     virtual ~wxMask();
 
-    bool Create(const wxMemoryBuffer& buf, int width , int height , int bytesPerRow ) ;
-
     wxBitmap GetBitmap() const;
 
     // Implementation below
@@ -71,6 +66,9 @@ public:
 
     WXHBITMAP GetHBITMAP() const ;
 
+    // implementation helper only : construct a mask from a 32 bit memory buffer
+    bool OSXCreate(const wxMemoryBuffer& buf, int width , int height , int bytesPerRow ) ;
+
 protected:
     // this function is called from Create() to free the existing mask data
     virtual void FreeData() wxOVERRIDE;
diff --git a/src/osx/core/bitmap.cpp b/src/osx/core/bitmap.cpp
index 5170f3f53b..fcfb40816b 100644
--- a/src/osx/core/bitmap.cpp
+++ b/src/osx/core/bitmap.cpp
@@ -1062,7 +1062,9 @@ wxBitmap wxBitmap::GetSubBitmap(const wxRect &rect) const
 
             maskbuf.UngetWriteBuf( maskbufsize ) ;
         }
-        ret.SetMask( new wxMask( maskbuf , destwidth , destheight , rowBytes ) ) ;
+        wxMask* const mask = new wxMask();
+        mask->OSXCreate( maskbuf , destwidth , destheight , rowBytes );
+        ret.SetMask(mask) ;
     }
     else if ( HasAlpha() )
         ret.UseAlpha() ;
@@ -1505,22 +1507,14 @@ wxMask::wxMask(const wxMask &tocopy) : wxMaskBase()
 wxMask::wxMask( const wxBitmap& bitmap, const wxColour& colour )
 {
     Init() ;
-    wxMaskBase::Create( bitmap, colour );
+    Create( bitmap, colour );
 }
 
 // Construct a mask from a mono bitmap (copies the bitmap).
 wxMask::wxMask( const wxBitmap& bitmap )
 {
     Init() ;
-    wxMaskBase::Create( bitmap );
-}
-
-// Construct a mask from a mono bitmap (copies the bitmap).
-
-wxMask::wxMask( const wxMemoryBuffer& data, int width , int height , int bytesPerRow )
-{
-    Init() ;
-    Create( data, width , height , bytesPerRow );
+    Create( bitmap );
 }
 
 wxMask::~wxMask()
@@ -1591,7 +1585,7 @@ void wxMask::RealizeNative()
 
 // Create a mask from a mono bitmap (copies the bitmap).
 
-bool wxMask::Create(const wxMemoryBuffer& data,int width , int height , int bytesPerRow)
+bool wxMask::OSXCreate(const wxMemoryBuffer& data,int width , int height , int bytesPerRow)
 {
     wxASSERT( data.GetDataLen() == (size_t)(height * bytesPerRow) ) ;