Tom, this from our Emeritus Guy. The picture, incidentally, was taken August 11, 1937, about 9 years after regular passenger service was discontinued.
The last scheduled First Class (Passenger) trains from/to Michigan City were #9 and # 14 (both to/from Lafayette) on CIL Emp TT #51 of 02/19/28 (superceded 05/06/28),
The next TT (#52) had "new" trains #132/133 scheduled as a Medaryville turn out of Lafayette. This
"turn" last appeared on CIL TT #60 of 07/27/30.
The last scheduled First Class Train was taken off by the time of CIL TT #61 issued11/22/31.
So, the last scheduled passenger service on the Michigan City Branch ended in 1931-2.