According to an entry in the Clan Cameron Archives, Loch Arkaig, west of the Great Glen, has a "lake-horse" that in the past was seen by a deer stalker and his children.
Mr Cameron denied his campaign to solve the so-called "West Lothian" question - where Scottish MPs can vote on issues which affect only England like health, law and order and education but not vice versa - was pandering to a "little Englander" agenda.
In a speech in Oxfordshire, Mr Cameron described the disorder that spread from London to parts of the East and West Midlands, Merseyside, Bristol, Manchester and Gloucester as "a wake-up call for our country".