540. Claim by mortgagee and those claiming under him.

A claim on the covenant for payment1 contained in the mortgage deed can be brought by the mortgagee and those claiming the mortgage security under him, whether by devolution on death2 or by alienation inter vivos. Accordingly, if the mortgagee has not assigned the mortgage, the right to sue passes on his death to his personal representatives, and, if he has specifically bequeathed the mortgage, the mortgage debt and the right to sue for it will vest in the legatee upon the executors' assent to the bequest being given