I take your point Nigel, but they are a small number compared to the C, Q and K Manx surname patterns. Has anyone managed to trace the MacYlxt, MacKyle, Macilvorrey etc ancestral lines back through this period?

Was the Mac actually part of the heriditary surname or was it still denoting 'son of' - I note some Ilchrist surnames for baptisms of daughters in the early German parish registers whereas sons at this time were entered as McYlxt - these may be different families, the minister's preference in transcription or the same family.

Just a simple question: could it be that all the Mac*** names were converted to C, K and Q*** names in 14-15th centuries through legal/social/autocratic pressure and that these represent a new wave of immigrants or religious conversions. Evidence either way anyone?