I read somewhere that the human mind can only remember a limited amount of
information. That is, we can only remember a limited amount per day, and
also we can remember only a limited total amount. So, for instance, a
person can recite the entire Bible or Koran, but no one remembers every
word of more than a very few books. If you try to remember more, then you
start to forget something else. Still, we have all heard of prodigious
feats of memory: singers who know every note, word, and nuance of hundreds
of songs; music lovers who can identify a piece after a few notes have been
played.
 
Which brings me to a question about shell species. How many molluscan
species can a person reliably recognize? Are there any
conchologists/malacologists who are, or were, famous for their memory? And,
on a more practical note, how is it done?
 
Andrew K. Rindsberg
Geological Survey of Alabama