Nice looking 110D indeed! Love these Nightfighters. In general I think it wasn't all that uncommon for a 110 to have the rear folding canopy piece removed (there's a few good examples from the 1940/1941 Zerstorer period), but I'm not quite sure if, and if so, to what extend this was done on these early night fighters (since they did not have all that much opposition from enemy night fighters/intruders I imagine there wasn't all that much reason to remove the canopy in the freezing cold when chasing bombers @ some 20.000 or so ft). There's a few very nice pictures indeed of this particular kite that might be helpful to establish wether such was the case with this aircraft, such as this one from Luftwaffe Im Focum #04