Initial Letters following Prefixes

Initial letters following prefixes are sometimes dropped thus:—

McCuskerMcUsker.
McClureMcLure.

One initial letter is substituted for another, as—

McIlmoyleMcElmoyle.

Or the letters following the prefix transposed,

McElroyMcLeroy.

The letter “C” is sometimes repeated after “Mc,” as—

McAdamMcCadam.
McArdleMcCardle.