Just to summarize tester's big find:
John B. Senasac =
Jean Baptiste Sénésac
born or baptised 08 Sep 1844
St-George-de Noyan, Henryville, Iberville, Quebec, Canada
son of
Cyprien Sénésac - parents Joseph Senesac & Margaurite Laberque
and
Julie Giboleau - parents Joseph Giboleau & __ Dautrepart