It could be the bride's brother 's signature - initialed in Hebrew:  י מ (yod, mem).
--
Steve Goldberg
Jerusalem, Israel
Researching:
Sagan/Shagan family from Veliuona (Velon), Lithuania
Goldberg family from Vidukle, Lithuania
Susselovitch/Zuselovitch family from Raseiniai (Rossein), Lithuania