AKA (Helmsley's) Old Morocco Barb
"about 1653 Fairfax bred Old Bald Peg to the Old Morocco Barb, probably one of four stallions presented in 1637 to Charles I by the Emperor of Morocco. The outcome was Old Peg, known more commonly as the Old Morocco Mare. It is this General Stud Book connection which establishes the pre-Christian Irish Hobby as a prime source of Thoroughbred sprinting speed."(Speed and the Thoroughbred" by Alexander Mackay-Smith, pub:Derrydale Press, 2000 (page 3)
Modern day grey Thoroughbreds do not trace back to this Sire. Modern Thoroughbreds trace back to the sire Crab.