generating source

The death became the generating source of definite accessions to the survivor's property rights. Although the property here involved was held under a joint tenancy with the right of survivorship created by the 1915 transfer, the rights of the possible survivor were not then irrevocably fixed since under the state laws the joint estate might have been terminated through voluntary conveyance by either party, through proceedings for partition, by an involuntary alienation under an execution. The right to effect these changes in the estate was not terminated until the cotenant's death.