By representation means a disposition or distribution of property made in the following manner to persons who take as issue of a deceased ancestor:
The property so passing is divided into as many equal shares as there are (i) surviving issue in the generation nearest to the deceased ancestor which contains one or more surviving issue and (ii) deceased issue in the same generation who left surviving issue, if any. Each surviving member in such nearest generation is allocated one share. The remaining shares, if any, are combined and then divided in the same manner among the surviving issue of the deceased issue as if the surviving issue who are allocated a share had predeceased the decedent, without issue.