Tyrell Research

I am looking for Ancestry information for Patrick Tyrell , born 1831, who married Catherine Nolan in St Peter's, Athlone on Jan 4 1855. His Father was John Tyrrell, born 1816 and Mother "Celia".  All are passed away with John and Catherine buried in St Charles cemetery, Blackstone, Mass., USA.  Their headstone states they are "natives of Caltra, Galway Ireland". I cannot find birth certificate in Galway for John or Patrick or Catherine Nolan! I do find them registered in DUblin....is that where records were kept at that time??  (early 1800's)

 

Sheila B