Plate under carb?

I just picked up a 1977 MGB. I have taken off the carb to rebuild it, and between the carb and the manifold there is a plastic plate with what appears to be a heating element in it. The plate has one electric wire hooked to it from the harness, and a plastic "bulb" about the size of the end of a thumb sticking out of it where the wire attaches. Is this device some kind of heater for the intake air? What would happen if I took it off? I have a cheap service manual for the car (a good one is on the way to me in the mail as we speak), and this cheap manual doesn't show the plate. Thanks in advance for any input. Keith