Wrong notification text when deleting series

Steps to reproduce:
1. Create two Series
2. Delete both Series using Actions->Delete

Actual Results:
Both series are deleted. A notification says "The event has been deleted".

Expected Results:
Both series are deleted. A notification says "The series has been deleted".
Even better, the notification would says "<N> series have been deleted", but that would be a feature, not the bug this ticket refers to.

Workaround (if any):