Something very strange going on here I think-
index to civil registrations (all Ireland)- no Lenmans
IGI (
www.familysearch.org)- no John Lenman
Emerald Ancestors index- no Lenmans
1912 Ulster Covenant- no Lenmans
PRONI Will Extracts- no Lenmans
1911 census only a few households on Jackson St., Belfast so number 642 doesn't seem to make sense
I did, however, find some interesting possibilites in England to consider-
John Lenman- BIRTH- registered Oct./Dec.1878 Bethnal Green district, London
1891 Census- London County Council Industrial Schools, Feltham Middlesex-
John Lenman, 12, inmate, born Holloway London
16 Jan.1927 "Metagama" arrived Liverpool, England from St. John, New Brunswick, Canada- going to 197 Moss La. E. Moss Side Manchester
John A. Lenman 48, bridgeman
Amy B. Lenman, 5