I have made a detailed study of the parish of Magilligan for the early modern period, [1600-1800]. In the period before civil registration the spelling of surnames was not standardised and there are often variations for a number of reasons: The names in these documents were entered by various officials who may have spelt the name phonetically in a way that made sense to them. The spellings of some surnames in the documents such as hearth rolls or Flax Lists are completely different from their modern equivalents. For example, the surname Brewster was rendered as Broster or Browster in most of the documentation for Magilligan.
And I have also noted the surname POLLOCK as POAGE, POAKE, POCK, POCKE, POGE, POKE, POLKE, POOK, and POOKE in various census substitutes in the period 1600-1800.
Magilligan surnames 1600-1800:
Abullon, Adams, Aken, Akin, All, Allen, Allin, Allison, Anderson, Armstrong, Aul, Aull, Bacon, Baird, Bailie, Barbour, Barnaby, Baxter, Beard, Begley, Bennett, Beresford, Berriman, Berrisford, Bigon, Blair, Black, Boyland, Brazier, Bresland, Brown, Broster, Browster, Bruce, Buchanan, Bullion, Butcher, Butler, Caldwell, Calhoun, Calwell, Callwell, Caldwell, Calhoun, Campbell, Canning, Canon, Cannon, Cargill, Carson, Carswell, Caruthers, Cassidy, Catherwood, Charleton, Church, Clarke, Clerk, Clinton, Clyde, Cochran, Coile, Colgan, Cook, Cooke, Coningham, Conn, Connell, Conner, Connor, Conyngham, Cowan, Coyle, Cox, Craig, Cramsay, Cramsey, Crampsay, Crawford, Cravens, Cree, Crisswell, Crocht, Crow, Cumming, Cunningham, Curry, Cushaglenn, Cust, Daniel, Darcie, Davis, Dealk, Deanes, Deeny, Deighan, Delap, Dennis, Diarmond, Dicky, Dirmond, Diver, Dogherty, Dohardy, Doherty, Donnelly, Doogan, Dougan, Dougherty, Dover, Drennen, Drummond, Dunlap, Dunn, Dyermond, Eaton, Ennis, Erwin, Farson, Fleming, Flimen, Flyming, Fowler, Fry, Fulton, Gage, Galt, Gallaughan, Gamble, Gibson, Gifford, Gill, Gillan, Gillen, Gilland, Glen, Glenn, Glendening, Goggins, Gorges, Graham, Granaghan, Green, Greg, Grigg, Haines, Hall, Hamilton, Hamson, Hampson, Hanna, Hassett, Hasson, Havlan, Haynes, Hayney, Hemphill, Henry, Hiland, Hill, Holly, Holms, Hopkins, Horner, Houston, Howard, Hully, Hutton, Innes, Irwin, Jack, Johnson, Kane, Kean, Kelly, Kelsoe, Kemkin, Kilmary, Killcriest, Kilmerry, King, Knox, Lane, Lawrence, Leake, Leathes, Leather, Leck, Lecky, Lee, Leek, Lenox, Lin, Lingard, Linton, Lochrey, Lochry, Loghlan, Long, Lurting, Lynch, Lyon, Lynton, Macknamara, Mackivor, Makrakan, Macrea, Madie, Magee, Magilligan, Magomery, Mainson, Major, Marshall, Martin, Maxwell, McAllman, McArthur, McAtire, McCain, McCallion, McCarter, McCausland, McClary, McClay, McClean, McClelland, McClernan, McClery, McCloskey, McColgan, McCome, McConel, McConncy, McCoy, McCormick, McCrakan, McCrackin, McCray, McCummins, McCune, McCurdy, McDermot, McDougal, McFeely, McFiely, McGeehan, McGivigan, McGranachan, McGrannahan, McGrorty, McGuggin, McGuy, McIntyre, McKane, McKeag, McKinny, McKinzy, McKnogher, McLaughlin, McMains, McMechael, McMullen, McMunity, McNeill, McPherson, McPoil, McSanic, McWilliam, Meacon, Mellon, Michaell, Michel, Mikle, Miller, Miskemin, Miskimmin, Mitchel, Monteeth, Moody, Moore, Moorehead, Mudie, Mulholland, Mullon, Murghland Muskimmin, Neille, Nelly, Nicholas, Nicholson, Nivenson, Nivins, O’Bonon, O’Brien, O’Byrne, O’Caen, O’Carran, O’Cathan, O’Doghertie, O’Dogherty, O’Gallogher, O’Hampson, O’Linn, Oliver, O’Lotharge, O’Lyne, O’Mullan, O’Sheale, Osborne, Park, Pattin, Pane, Payne, Pherson, Phillips, Plain, Pocock, Pogue, Priestly, Quig, Quigley, Quin, Ray, Read, Rey, Reynolds, Ridgate, Robb, Robinson, Rodger, Roger, Ross, Rowley, Rowth, Ruth, Scott, Shale, Shanon, Shearer, Sherer, Sherrard, Shiel, Shipboy, Short, Sinclair, Singard, Sinniard, Small, Smith, Snell, Span, Steevenson, Stewart, Stirling, Stoop, Stunkard, Sumers, Sweeny, Syniard, Tate, Taylor, Thompson, Thornton, Thorp, Till, Tittle, Tomlinson, Townsend, Tyler, Umry, Wallace, Wat, Ward, Warden, Wark, Webster, White, Whyte, Williams, Williamson, Wilson, Woods, Woodsyd, Work, Wray.