Some weeks ago I posed a question as to "What happened to Maryland?". I got a few replies but decided to do a bit of research on my own. The one interesting thing that I found, was that Maryland didn't have a clause in it's own state Constitution to protect the rights of individuals to bear arms. It's still a mystery to me though.
http://www2.law.ucla.edu/volokh/beararms/statecon.htm
http://www2.law.ucla.edu/volokh/beararms/statecon.htm