I am greatly interested in coiling abnormalities, primarily reversals of rotation (dextral/sinistral), translation along coiling axis (orthostrophy/isostrophy/hyperstrophy), and also disjunct whorls (open coiling).

An orthostrophic gastropod shell (eg Buccinum) grows by accretion of an apertural rim following a generating curve that is constantly translating in a "downward" direction along the axis, ie anteriorwards or in the direction of the siphonal canal, if present.

An isostrophic shell (eg Monoplacophora; there are no truly orthostrophic gastropods, unless bellerophontids are not monoplacophorans; the freshwater gastropod Marisa approaches this condition) is planispiral, with no translation.

In hyperstrophic shells (eg the dextral, but apparently-sinistral, Lanistes and Limacina) the direction of translation is the opposite to that of orthostrophic forms, ie it is in an "upwards" or posteriorwards direction. This makes a mockery of the terms "adapical" and "abapical", as each term can mean either direction, depending on strophy. Nonsiphonostomatous dextral hyperstrophic shells look much like normal sinistral ones (hyperstrophy occurs occasionally in specimens of New Zealand's Turbo smaragdus). A siphonostomatous hyperstrophic shell such as an abnormal Busycon would look wierd, with sunken spire and the canal wrapped around the penultimate whorl, looking probably like a giant spiny Bulla (I'd dearly like to see such a specimen).

It's amazing how few authorities realize the difference between "sinistral" and "hyperstrophic", regularly confusing the two. Just check in any book you care to; look up Architectonicidae, Pyramidellidae...these all have dextral, though hyperstrophic, protoconchs.

Heterostrophic shells such as pyramidellids and other opisthobranchs have a hyperstrophic protoconch with an orthostrophic teleoconch.

I would appreciate any information on coiling abnormalities, even if it's only the names of species observed to be abnormal.

I would also like to obtain specimens (especially abnormal Epitoniidae!). This includes specimens of marine gastropods which are normally sinistral. At the moment my colection includes very few, including a hyperstrophic Turbo smaragdus and a sinistral Cirsotrema zelebori.

Andrew Grebneff