(d) where, the mortgagee being entitled to possession of the mortgaged property, the mortgagor fails to deliver the same to him, or to secure the possession thereof to him without disturbance by the mortgagor or any person claiming under a title superior to that of the mortgagor: Provided that, in the case referred to in clause (a), a transferee from the mortgagor or from his legal representative shall not be liable to be sued for the mortgage- money.