I'll end my alphabetical list with another unknown and no doubt another pseudonym. He or she was Aalla Zaata. I doubt that any person has ever borne that name. Mr. or Ms. Zaata wrote one story for Weird Tales from 1935.
And so ends my A to Z list.
Aalla Zaata's Story in Weird Tales
"A Grave Is Five Feet Deep" (July 1935)
Update (Mar. 7, 2017): According to a reader, Aalla Zaata was the pen name of Dora Black Russell, also called Winifred (Brent) Russell, also called Dora Winifred Russell. I will do further research and write a new article about her as time allows.Text copyright 2013 Terence E. Hanley