Try Mead's book on Achatina fulica published in the 1960's.  "The Giant
African Snail:  Economic Importance" or something like that.

Kurt

At 11:57 AM 6/23/99 +0200, you wrote:
>In my garden my daugther  Margo found a live specimen of Helix aspersa, with
>a thirty white mites crowling (0,1 - 0,2 mm) over the animal and going
>inside through the respiratory opening. (Helix aspersa is too common in my
>garden and I 'll examine other specimens)
>In my little library I could not find a paper about snails and mites living
>together or parasitory mites. Is there anybody who has made the same
>observation and is there some literature about this subject?
>M.C. Cadee, the Netherlands.
>