The following information is taken from the Dictionary of the Older Scottish Tongue, available online at http://www.dsl.ac.uk/index.html. This is a work in progress.
| Spelling | Number | Dates & headers | 
|---|---|---|
| Foullis | 3 | 1592 (big, cost), 1643 (cunȝe-) | 
| of Foullis | 1 | 1583 (cautionarschip) | 
| Foulys | 1 | 1465 (conjunctioun) | 
| Fowles | 1 | 1596 (counterfute) | 
| Fowlls | 1 | 1596 (burges) |