diff --git a/transition.go b/transition.go
index 6f95f8e..c5687ab 100644
--- a/transition.go
+++ b/transition.go
@@ -42,6 +42,6 @@ func (r *Transition) Subscribe(s Subscriber) {
 
 func (r *Transition) Notify(on Eventtype, source State, dest State) {
 	for _, s := range r.subscriptions {
-		s.Notify(&EventMessage{On: On, Source: Source, Dest: Dest})
+		s.Notify(&EventMessage{On: on, Source: source, Dest: dest})
 	}
 }