According to the website "The Online Institute for Advanced Loyalist Studies" http://www.royalprovincial.com/military/mems/mems.htm
It defines "Memorial Claims" as:
Among the more important sources of information for both genealogists and military researchers are the memorials (or petitions) written by the Loyalists themselves, mostly after the war, for compensation of losses sustained.
These memorials usually provide information concerning residency, family, military service, property, profession, etc.
The usual recipients of these memorials were the commissioners appointed by act of Parliament, charged with determining the validity of the claims and amounts of compensation.
I havn't found out which lot he received but his grandson, John Alexander Grant (my 2nd Gr Grandfather) is listed on 1st Consignment Front; western half of Lot 24 in 1879. I don't know if it was Alexander's or Richard's (his son who also claimed land for being a son of a UEL).