Thanks for your quick responses. I think the Alma who died in 1923 would be the same Alma as the one on 1920 census born 1912. The reason I say this is because her mother, Marie (or to us in the UK - Aunty Mary) told my mother when she stayed with the family in 1946 that she had had a child that had died. She and her "husband" Plant did travel on the ships between NY, Hamilton, Bermuda etc for some years with his job on ships. So that information is correct.
The Marie Plant found died 1947 in Manhatten I am sure is her too. I knew before that her widowed husband ended up marrying again and living in Florida, through some kind person on rootschat who informed me, so I have all this information, as you see on my tree.
I also know that they went through a marriage ceremony at a catholic church in NY City in 1933,. I have a copy of the notice sent from that church to Mary's parish where she was born in Rochdale informing thm of the fact. Here is the mystery, when she left England in 1911 she was to meet her husband "Harry Shoesmith"who had gone the year before her. Something happened because he told the tale that she never "got off the ship" and he didn't know what became of her. In fact it was in the early 1960s that he got in touch with his family in the UK to try and find out what happened to her. When I found the notice at the church in Rochdale saying she was married in 1933, did she get a divorce from Harry? Or did she assume he was dead? Anyway, according to the census records she styles herself "Mrs Plant, wife" so perhaps they were living "over the brush" as they say in England - co-habitating. What do you think? My father always said, and I quote "she was always a mystery" and I am beginning to think he was right!
PS She had already had one child a boy who died probably just after birth in the UK prior to them emigrating to the USA.