Well it has been a couple of years since I opened up the Necronomicon and
even then I was interrupted by the Rare Book Dept. staff once they
discovered that my Harvard library card was fake. So I don't remember
this distinction being made, but it is quite possible that the
Necronomicon makes the same point as Ludvig Prinn's De Vermis Mysteriis.
Prinn, when describing his arrival in Chorazin, makes the point that "the
Great Old One, Cthulhu, who is trapped beneath the waves yet has a power
over men's minds during slumber, can only affect the world through its
Will. A Will that has the power of movement without body and the ability
to create visions within mind." Prinn later goes on to call this Will of
Cthulhu, the Chorazin and describes how the city of Chorazin named itself
after this Will. An interesting read but not relevant to your question.
Anyway, maybe the Necronomicon simply calls the Chorazin by the name
C'tulu. Hope this helps.
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