Gloucester Road platform lighting

Here are a few shots of the platform lighting at Gloucester Road underground station. I've not come across fixtures like this anywhere else on the system, does anyone know what they are..? I can't decide if they're MV or MH, but it's certainly an interesting design.

Unfortunately the camera doesn't allow much in the way of exposure control. Looking at it with the naked eye, it's possible to see the construction of the lamp, which is clear elliptical. I think they're MV but it's hard to tell with them lit, so they could be MH.