At LDS Family Search, Selby's marriage record shows his father as Edgar and mother as "Salina Semer". At David Pike's "My family history page" at www.math.mun.ca
, Selby's baptism is transcribed as May 1876 at Harbour Grace South, parents are Edgar Noseworthy and Selina Seymour, abode is South Side. There are also baptism records for brothers David and Jacob, March 1873, and Leander, 1879.
There is a Selby "Nasworthy" living at Winthrop, Suffolk, Massachusetts, in the 1910 census....marital status is single. Is this your ancestor? If so, why is he listed as "single"....do you know?