From book by F.A. Battey, Biographical Souvenir of the State of Texas, Southern Historical Press 1978:

John D. Bourn is a native of Missouri and was born August 5 1850.  His father, William Bourn, was born in Kentucky, but moved to Missouri in an early day, where he was one of the leading farmers in his county.  He was a Mastor Mason, and a justice of the peace for Scotland County.

Full snippet here:

http://johnsonfamily.talldude.net/gensource/view_source/2218/john-d-bourn-biographical-souvenir-of-the-state-of-texas-containing-biographical-sketches-of-the-representative-public-and-m