Dan,
 
I would love to have a specimen of Monodenia fidelis!  I too am somewhat
limited in trading as most of my stuff is not self collected but
purchased from dealers.   When I have duplicates for trade it usually
means I bought a synonym of a species I owned (I've done it twice for
Conus sowerbyi/praecellens - would you like one?) or I just goofed and
ordered the same shell twice, or I may have found a deal on a bunch form
the Philippines or India (Oliva minicea, Cypraea caputserpentis, Planaxis
sulcatus, Nassarius stolatus, Nassarius globosus - all available).  I am
afraid I cannot offer much in the way of California shells for your wife
- but I do have a few.  By the way, what is S. californa?  Couldn't find
one in any of my books.
 
Donax punclatostriatus          22mm    F       Baja
Oliva incrassata                53mm    F       Baja
Olivella biplicata              15mm    F-/F    Baja
Terebra armillata                8mm    F       Baja
Thais biserialis                22mm    F-      Baja
Pitar lupanaria                 15mm    F       Baja (?)
Megathura crenulata             70mm    F-      Cal
Mitra idae                      35mm+   F       Cal
Murex festiva                   32mm    F       Cal
Crassostrea gigas               82mm    F-      Cal
Acanthina paucilirata           14mm            Cal
Caliostoma ligatum              17mm    F-      Cal
 
And of course we have the local Helix aspersa, introduced to New Mexico
in the early 1950s in shipments of roses from California where it paused
on its way from Europe.  There is another one I've heard of which has
established itself in the downtown area but I haven't seen it and do not
know what it is YET.
 
I am not certain of the data or condition of the shells above as this was
just a quick grab from my database and I haven't looked at the shells.  I
just noticed the Crassostrea gigas and if I'm not mistaken, I bought
those at a fish market in Seattle (almost California!!).  Anyway, if you
would like any of them, please let me know.  No need to worry about a
trade as I'm already in debt for the Otala lactea you sent a while back.
 If, as I suspect you already have better specimens than the ones I can
offer, let me know if you are interested in a particular family that is
not a California species and I'll see what I have.
 
I am now the proud owner of a Cryptochiton stelleri from your area I just
bought on the Raine's auction.  I also got some pictures of the living
animal from the internet and I must say it is a bit ugly - but it sure is
big!
 
BREAK----BREAK----BREAK----BREAK
 
I just re-read your letter and realized you were trading California
shells, not wanting them (which makes all kinds of sense).  Well, my
excuse is I've been laying patio blocks in the back yard all day and I'm
a bit light-headed (more than usual).  I'm going to leave it as is.  Let
me know if you want any of these and I will get the list I sent to Carlos
in Italy and forward it to you.  You might find something you like on it.
 
Sorry about the rambling, no more blocks today,
 
Tom Eichhorst
4528 Quartz Dr. N.E.
Rio Rancho, NM 87124-4908
 
P.S.  I still owe you some New Mexican endemics if, no when, I find them.