Aydin Orstan asked on Conch-L 7 Jan 1998 if Pilsbry's monograph is still
the only authoritative work on land snails of north America.
   Pilsbry (1939-1948) is still an essential text for land snail researchers
in north America.  Yes, a number of new taxa have been described, and there
have been some nomenclatural changes, but Pilsbry's monograph remains sound.
   If you can find it, try also: Burch, J.B. 1962. How to know the eastern
land snails, Pictured Key Nature Series, Wm C Brown.  It is an excellent
summary of Pilsbry's monograph, but unfortunately it has been out of print
for decades.
   You can see some of the new taxa since Pilsbry in a paper by Walt Miller,
R.L. Reeder, N. Babrakzai & H.L. Fairbanks.  1984.  List of new and revised
recent taxa in the North American terrestrial Mollusca (north of Mexico)
published since 19 March 1948.  Tryonia, No. 11.  -- only for Pilsbry's
volume 1: basically Helicoids and Polygyrids.
   You can get a handle on the current gastropod names using "Common and
Scientific names of Aquatic Invertebrates from the United States and Canada:
Mollusks", American Fisheries Society Special Publication 16, by Donna
Turgeon et al., 1988.  By the way, a second edition of that work has been
due since 1993, so it might be out any day.  I saw a preliminary draft of
part of the 2nd edition and it included helpful justifications for changes
made since the 1st edition.
   To toot my own horn, you could also try Burch, J.B. & Pearce, T.A., 1990.
Terrestrial Gastropoda.  Pp 201-309 in Dindal, D.L., Soil Biology Guide,
John Wiley & Sons.  That paper will get you to genus for land snails and
slugs in North America north of Mexico.
   I hope these suggestions are helpful, and I am glad to hear about another
land snail enthusiast.  Best wishes,   -Tim-
   Timothy A. Pearce, Curator of Mollusks
   Delaware Museum of Natural History
   Box 3937, Wilmington, DE 19807, U.S.A.
   phone (302)658-5004 or 658-9111