Sir W. Scott's famous Scotch greyhound, Maida, had this habit, and it is common with terriers.
"The Expression of Emotion in Man and Animals" by Charles Darwin
I thought of a Scotch terrier at the sight of his shifty eyes in the glade between his tangled hair and beard.
"Options" by O. Henry
They call him a Scotch terrier.
"My Lady's Money" by Wilkie Collins
He snarled like a Scotch terrier through his ragged beard.
"Heart of the West" by O. Henry
His hair did not stray over his eyes, ears, and coat, like that of a Scotch terrier, but had got itself cut.
"Democracy An American Novel" by Henry Adams
His head and face and eyes made one think of a little Scotch terrier.
"The Prospector" by Ralph Connor
By his side trotted painfully a wiry, yellowish, footsore Scotch terrier.
"Lucretia, Complete" by Edward Bulwer-Lytton
Lost, a Scotch terrier, by a gentleman, with his ears cut close.
"Practical Exercises in English" by Huber Gray Buehler
The one was a Scotch terrier, gentle and ready to fraternise with all honest comers.
"The Human Side of Animals" by Royal Dixon
Our room was 210 and the next was 212, and there was a old maid with a scotch terrier occupied 212.
"Peck's Bad Boy and His Pa 1883" by George W. Peck