Number 295. Helen McCloy (1904 - 1994), aka Helen Clarkson wrote more than 30 mystery novels, plus many short stories. She was educated at The Friend's school in Brooklyn and at the Sorbonne in France. She was also married to Davis Dressler (aka Brett Halliday), author of the Mike Shayne mysteries.
Number 305. I guess I'll start including large scans of the maps, too. The Million Year Picnic is also the name of a venerable Cambridge, Mass comic-book store.
Number 104. Cleve F. Adams (1895-1949) also wrote the screenplay for "The Fatal Witness" (1945) starring Evelyn Ankers.