As no two of the men had the same color hair, there must have been one blond, one red, and one black; and the same must be true of the women, as there were two of each color hair in the room.
Miss Terry was in room at time of murder; she did not know where Miss Thomas was at that time. As Miss Mills was with Miss Thomas at the time of the murder, neither of them could have been in the room; so neither could have been the murderess. We therefore place an X before their names.
There were three in the room (beside Thomas) when the murder was committed; two of them had the same color hair, so must have been of different sexes; the killer's hair was of a different color. Miss Terry was there; and as both the other women were out of the room, Miss Terry and two men must have been there. Miss Terry and one of the men must have had the same color hair; therefore the third person must have been the murderer, and was a man.
The killer had the same color hair as either Miss Thomas or Miss Mills.
The butler's hair was either red or blond, because it contrasted strikingly with Miss Mills' black hair; and he must have been one of the two men in the room, in order to know definitely who was in t he room at the exact moment of the murder.
The killer did not have the same color hair as either of the other two men, and as he had the same color hair as one of the guests who was absent from the room it must have been the same color as Miss Mills', which was black, as she was the only woman guest absent from the room; therefore the killer had black hair.
The butler could not have been the killer because his hair contrasted strikingly with Miss Mills', and we X him out.
So either Perry or Wayne must be the killer.
As Miss Mills was the only girl with black hair, Wayne's hair could not have been black, as it was the same color as Miss Thomas's, and so we X Wayne out.
Therefore it was Perry whom Muldoon arrested.
The Murder Mystery Puzzles of Edgar Rice Burroughs Vol.1 Page 3