premise: The Bavarian Mountain Hound (German = "Bayerischer Gebirgsschweißhund") is a breed of dog from Germany. As a scent hound, it has been used in Germany since the early 20th century to trail wounded game. It is a cross between the Bavarian Hound and the Hanover Hound.
hypothesis: The Bavarian Mountain Hound is found in London. 
reason: Just because it comes from Germany doesn't mean that someone hasn't got the dog and brought it to London. It may be able to be found in London now. 