Definition: Taking by representation; the group or class receives by representation and in equal shares what their deceased parent would have been entitled received. The common usage is "to my then living descendants, per stirpes." If you have two children and five grandchildren who survive you, then each child will receive a 1/2 share and the grandchildren will receive nothing. If one of the children predeceases you and is the parent of three of the grandchildren, then the surviving child will receive a 1/2 share and each granchild will receive a 1/6 share (or the deceased child's 1/2 share is divided equally by the three children who have survived the deceased child = 1/6 each).
Contrast this to "per capita," or by head count: "to my then living descendants, per capita." In the above example with two children and five grandchildren who survive you, the children and grandchildren will each receive a 1/7 share.

