It is not pleasant to be overlooked, and it definitely makes sense to look over any situation where this may be occurring. However, the first order of business is look at your own actions.
For example, when you attend meetings, do you interrupt, disrupt, or distract the group? Are you typically ill-prepared? Outside of these meetings, do any of your behaviors set the stage for his reaction in these meetings?
Assuming you have done nothing that would cause his unacceptable behaviors in his meetings, you need to have a different meeting, namely with him. Tell him that you would like to play a more active role in his sessions, and then give him specific examples of the ways in which you have been overlooked. Let him know how you feel about this and tell him that you expect to be treated as an active participant in these meetings. Then ask for his thoughts.
Based on what he says and does, you should not have difficulty in determining what you should say and do from there. Of course, the larger question is whether you need to attend these meetings at all. If you are being ignored in these meetings, perhaps you can ignore them. | 
