Lucinda is hubby's 2d great-grand aunt, the older sister of Lucy E. Bentley, who married great-great granddad Brice S. Larimer.
Just three weeks ago, my query posted on Ancestry's Bentley message board put me in contact with a Bentley researcher who had traced more of the Bentley children, finding Lucinda and Lucy in Elkhart county and learning that the rest of their siblings had journeyed to California in search of fertile farmland and a bit of pioneering adventure.
At his suggestion, I sent for Lucinda's death record. Meanwhile, I also contacted the wonderfully knowledgeable and helpful folks at the Elkhart County Genealogical Society, who sent me the above photo (along with at least a dozen other photos of Larimer family tombstones from Elkhart County).
According to Lucy Bentley Larimer's death doc, William Tyler Bentley and Oliver [sic] Morgan are her parents. Now we want to confirm by reading the names on Lucinda's death cert.