A very similar but not identical shot can be found in Newel Hart, Hometown Album (Preston, Idaho: Cache Valley Newsletter Publishing Co., 1973), no. 656. Linda says she wrote the names on her copy before she knew better. Here are the identities, from both sources:
Front, left to right:
Jim Hobbs, Martha Catmull Hobbs*, William Hobbs, Olivene Hobbs (child), Matilda Barrett Hobbs (William's wife, "Till"), Charles W. Hobbs, Mary Ann Hobbs (his wife), Edith Hadlock, Caroline "Kitty" Watterson, William Watterson.
Unknown (or Jim), Oscar Halgren, his wife Minnie Halgren (they ran a hotel in Franklin), Mary Ann Webster Hobbs (Wilford's wife), Wilford Hobbs (hotel owner), Charles R. Hobbs, Tom Hobbs (or Hugh Hadlock), Ida Purnell Hobbs (wife of Charles R.), unidentified, Rose Hawkes, Melissa Smith, A. Carl Smith, Nessa Parkinson Hobbs.
Young man in bowler hat at bottom of arch on our right is Bernice R. Parkinson. Next to him is Anita Parkinson Smoot. Behind Wilford Hobbs is Myrtle Hobbs Kennedy. Her husband Dan Kennedy is behind Charles R. Hobbs.
*Hometown Album identifies this as Louisa Driggs Purnell, but a photo of James and his wife Martha in Alice C. Cardon's This Is Benson: Cache County, Utah, It's History and People (1982) is very similar to this.