Hi Phil, thanks for your thoughts, which coincide with my take on the situation. The naming in the 1910 will of Thomas Selby of Boulogne and Thomas Selby the younger of Lincolns Inn Fields (ie he was probably a barrister) refers back to an Indenture dated 15 July 1864, so I think the Thomas of Boulogne was the cricketer and the younger Thomas was his son, as you say, either the brother or half brother of Alfred.
I wonder if the baptism of Thomas Selby at St Pancras on 4 Feb 1819, son of Thomas and Louisa Cline Selby, solicitor, might be them. Must work on it! There's a marriage licence dated 24 Sept 1817 for a marriage between Thomas Selby widower of St Clement Danes, Middlesex, and Louisa Cline Coleman, 19, of Hythe, father Edward Coleman gent. If this really is Thomas the cricketer then he appears to have been married three times.
Is Thomas the cricketer your direct line (assuming he was Alfred's father)? I suppose it would take Alfred/Elizabeth's marriage cert to see if Alfred's father was Thomas, a solicitor
His cricket career according to Cricinfo was not illustrious - he played 3 matches for Kent, 6 innings, scored runs 19 runs in total, highest score 17 (which leaves only two runs for the other five innings!)
Full name Thomas Selby
Born November 4, 1791, Gillingham, Kent
Died May 7, 1874, Boulogne, France (aged 82 years 184 days)
David