Terry,
  If one of the German works you are refering to is Thiele's work, the
gastropod volumes are available in an English translation.  The bivalve
volume is currently in the works.  The translations were edited by Rudiger
 Bieler and Paula Mikkelsen.  I believe these volumes can be
obtained from the following address
 
National Technical Information Services
Springfield, VA 22161
 
for Thiele's Handbook of Systemic Malacology the catalog number is
 TT 81-52005.  Do not know what the cost is.
 
  The problem that still remains is the question of an up to date book.
Thiele was writen between 1929 to 1935.  Many new genera, subfamilies, and
families have been described since then.
 
Charlie
******************************************************************************
Charlie Sturm, Jr
Research Associate - Section of Invertebrate Zoology
                     Carnegie Museum of Natural History, Pittsburgh, PA
Assistant Professor - Family Medicine
 
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