diff --git a/include/wx/gtk1/bitmap.h b/include/wx/gtk1/bitmap.h
index 8c3111d588..f8b1d14912 100644
--- a/include/wx/gtk1/bitmap.h
+++ b/include/wx/gtk1/bitmap.h
@@ -69,7 +69,7 @@ public:
     wxBitmap( const char* const* bits );
     wxBitmap( const wxString &filename, wxBitmapType type = wxBITMAP_DEFAULT_TYPE );
     wxBitmap( const wxImage& image, int depth = -1, double WXUNUSED(scale) = 1.0 ) { (void)CreateFromImage(image, depth); }
-    wxBitmap( const wxImage& image, const wxDC& WXUNUSED(dc) ) { (void)CreateFromImage(image); }
+    wxBitmap( const wxImage& image, const wxDC& WXUNUSED(dc) ) { (void)CreateFromImage(image, -1); }
     explicit wxBitmap(const wxCursor& cursor);
     virtual ~wxBitmap();