In default of these, the law next names sisters by the same father and their issue. If these fail, it gives the right of succession as next-of-kin to the third degree, namely, first cousins on the father's side including their children. If this degree is also lacking, the law goes back and gives the succession to the relatives of the deceased on his mother's side on the same principles as originally regulated the rights of inheritance by the relatives on the father's side.