Many Ontario cenotaphs used initials instead of given names. An excellent site with full names and details is the Commonwealth War Graves Commission
contact John Allan if you are willing to transcribe a cenotaph or other war memorial for OGSPI
JACKETT
JACKSON
JACOBI
JACOBS
JAMES
JAMIESON
JARRETT
JARRETTE
JARVIS
JAS
JAUTRAS
JAY
JEFFERISS
JEFFERS
JEFFERY
JEFFREY
JEFFRIES
JEFFRY
JEFFS
JENKINS
JENKINSON
JENSON
JERMYN
JESSUP
JEWEL
JEWELL
JINKS
JOBSON
JOHNSON
JOHNSTON
JOHNSTONE
JOLLEY
JOLLY
JOLY
JONDREAU
JONES
JORDAN
JOSEY
JOSLIN
JOURDAN
JOYNT
JUFFS
JUHLIN
JUNKIN