Dear All,
  For my two cents worth on a good book, one need only look at Kevin Cummings
and Christine Mayer's book, "Field Guide to Freshwater Mussels of the Midwest.
I really like that format, although it would be impossible for a really large
book of varied species. Some of the things I liked were: The photo with the
description, a good description and a distribution map of the species,
habitat, holotype number and where deposited along with type locality and
similar species. Very very excellently done.
  I would like to see all shell books done in that way but know it would
probably be impossible due to color costs for the plates.
           Carole M