Noted Lovecraftian scholar S. T. Joshi has authored a criticism of Lovecraftian and Cthulhu Mythos fiction, beginning with the stories by H.P. Lovecraft that gave birth to the entities, locales, books, and other plot devices that have come to be known as the "Cthulhu Mythos". Joshi further details the works of August Derleth, Frank Belknap Long, Clark Ashton Smith, Robert E. Howard, Donald Wandrei, Robert Bloch, Fritz Leiber and other. Joshi then expounds upon the "Derleth Mythos", and its influence on subsequent Lovecraftian fiction. Joshi then explores a new generations of Mythos writers and their respective expansion of the Cthulhu Mythos, including Richard L. Tierney, Gary Myers, Brian Lumley, Ramsey Campbell, Michael Shea, Walter C. DeBill Jr. and others. Finally, Joshi reviews some of the more modern authors who have taken up the Lovecraftian mantle: Jeffrey Thomas, Stanley C. Sargent, Wilum H. Pugmire, Thomas Ligotti, Joseph C. Pulver and many others.