Hi Harry,
Do your transcripts come from National Archives emigration records? I have access only to the passenger entry records, after the twins were born. I was looking at these to see whether T M Davidson's second initial could have been mistranscribed, because I couldn't find him in NZ records, and he doesn't seem to have made it to the shores of NZ. Perhaps changed his mind about going, or got off at a port before NZ?
This is a transcript of the passenger list from the "Waikato" arrived Wellington 11 July 1874:
freepages.genealogy.rootsweb.ancestry.com/~ourstuff/Waikato1874.htm
Colonial Nominated Families and Children
Leece James 32 Isle of Man Farm Labourer
Margaret A. 31
John Alfred 7
Thomas William D. 5
James M. 1
Janet M. 1
I don't know how well this URL will work, but this is a scan of the volume:
ht tps://www.familysearch.org/search/image/show#uri=ht tps%3A//api.familysearch.org/records/waypoint/6794886
[please close the space in BOTH ht tps].
There is an index on p.2 which doesn't have Davidson. The index has James Leece p.16, and the image number is also 16 (although it has 14 at the top of the page). It has "Colonial Nominated Emigrants", with the total cost to the Govt being #58. There were various assisted immigration plans in the 1870s when NZ needed labourers. "Remarks" have "New Plymouth 49, 3 1/2 free".
I double-checked but couldn't find Davidson among the single men. The Single men "Colonial Nominated Emigrants" are on image 23. I didn't go to the end of the passengers, but stopped there. (Single women are on the next page.)
Sue