James,
Could it be that you misheard Petuch and that he was talking about Chemnitz
rather than Clench? All names by Chemnitz were ruled by the ICZN as invalid
with the exception of one - Conus gloriamaris. You will still find shells
offered with Chemnitz as the author - but this is in error. As for Clench:
Dr. William James Clench (1897-1984), Curator of Molluscs at the Museum of
Comparative Zoology, Harvard University from 1926-66. He founded and edited
"Johnsonia" in 1941 and among his students was one R. Tucker Abbott.
Tom E.
PS Hope everyone has a great Christmas (or whatever holiday you are
celebrating at this time) and New Year!