"Scollay's Reel" is a Shetland reel variant of the Irish hornpipe "King of the Fairies" and the two go well together in a medley.
The name "Scollay" is a fairly common name in the Shetlands and Orkneys and is a local name of Norse origin, unrelated to the Irish "Scully".
It was printed in Silberberg's Tunes I Learned at Tractor Tavern (2002) and Songer's Portland Collection (1997).
It was recorded by J. Scollay & P. Scollay on Da Mirrie Boys: Shetland Fiddle Music (1978), John McCutcheon on The Wind that Shakes the Barley (1977), Swallowtail on Swallowtail (1982) and others.
I learned this at our Monday night jam.