I suspect that is either BL's mis transcription or BL's uncorrected reading of the 1851 local Manx copy on which he based his first version of index - chk index on FHS site, if you have the IoMFHSoc paper copy check as that def used the local copy as basis (but tho always produced in Museum contains hundreds of errors + missing entries) -there are I'm afraid still a number of errors in BL when you compare with the CD images now available but much much better than Ancestry it appaers tho possibly they have got round to correcting their errors - my CD def reads much more like Manners than mcmanus, likewise the son's name is relatively clear on CD - however the 1861 is def Manners