Well not so strictly. It says bilberry or blueberry because what is exactly meant is not so black and white, and it may also depends on your flavour of English and French.
For instance, @bombela says that "North American" blueberry is 'bleuet' in Canadian French. In France, 'bleuet' is a flower.
"Vaccinium myrtillus" literally means the "common Myrtille". Which is not blue and doesn't taste like a blueberry. I understand that blueberry is the common North American English word for Bleuet an and Myrtilles. While it's the other way around in France.
Blueberies are called Bleuet in Canadian French. And in France today they are sold with the same two names on the packaging (blueberies, bleuet), but often people will call them myrtille anyways! A point of contention for me as I am alwahs sad to hear Myrtille and be served Bleuet :)
You probably mean the 'European blueberry', Vaccinium myrtillus.