Years ago I had a experience in a meditation and saw a ET who had a plate like structure like this as part of his head, he had no mouth per se, very tall and I felt he was a very peaceful type and kind. The impressions I received were that he was like a scientist or at least he had samples of many living things around him.
Perhaps this being is not from a past of ours but from a future?
Vinnie E. Allbritton