Arnstein & Lehr LLP announced this afternoon that it is in the middle of discussions to merge with a Philadelphia-based firm Saul Ewing LLP.In a statement issued around 2 p.m., the Arnstein’s executive committee chairman said talks are underway.“Arnstein & Lehr and Saul Ewing confirm that they are engaged in discussions about a potential merger. Both firms will continue discussions and will share more if and when it is appropriate,” partner Jeffrey B. Shapiro said.Saul Ewing LLP, which has 11 …