Hi,
 
By way of introduction...I am a collector/hobbyist, not a scientist, so
I'm not up on all the changes in the field.
 
I've  followed the discussion on Neverita, and have finally understood
that Neverita was originally Polinices. I accept the fact that Polinices
heros is now Lunatia heros, and that Polinices duplicata is now Neverita
duplicata, because, after all, in this imperfect world we must
constantly strive for perfection.  But I tripped somewhere along the
way.
 
Regarding the duplicata: in Field Guide To The Shells (Morris, 1960), it
is called duplicata; in Shells of the Atlantic & Gulf Coasts (Abbot &
Morris, 1995) it is called duplicatus.  In checking my shelf of books, I
would say that the two forms of the word of pretty evenly divided.
 
So, two questions. One is when did the name change to Neverita, and the
other is why the two spellings of the species name?
 
Anyone for answers?
 
MICHAEL
White Plains, NY