I recently discovered an obituary for Patrick Lawler (b. 1835, Ireland) that said that he arrived in New York aboard the ship "The City of New York" in July, 1865. And indeed, this ship landed in New York on July 31, 1865. The ship also made several other crossings that year. So, I think the information should be relatively accurate. The only problem is that I cannot find him (or his wife Margaret and child Michael) in the passenger lists for that year.
How many passenger lists are missing? And is it even conceivable that someone might be on the ship but not on the list?