Cornelius was born in Anna Regina, in what is now Guyana's Pomeroon-Supenaam region.
[1] He made his first-class debut for Guyana during the 1966–67 Shell Shield season, against Barbados.
[4] His season included two five-wicket hauls – 5/67 against Jamaica and 6/104 against the Leeward Islands.
[2] During the 1969–70 season, Cornelius finished as the leading wicket-taker for Guyana and third overall, with 16 wickets from his four games.
[6] Despite his successes, Cornelius played only one further season for Guyana, with his last first-class appearance coming in March 1971, against the touring Indians.