Section 2B. Except as otherwise provided in chapter one hundred and fifty-two, if, as the result of the negligence of an employer himself, or of a person for whose negligence an employer is liable under section one of chapter one hundred and fifty-three, an employee is instantly killed, or dies without conscious suffering, the surviving wife or husband of the deceased or, if there is no wife or husband surviving, the next of kin, who, at the time of such death, were dependent upon the wages of the deceased for support, shall have a right of action for damages against the employer. This section shall not apply to injuries caused to domestic servants or farm laborers by fellow employees.