David and others,

The O with a / through it is called 'slashed O' in English. It is used in
Danish and Norwegian; Swedish uses the O umlaut instead. If you are curious
about such symbols, a good source for more information is:

Bringhurst, Robert, 1996, The elements of typographic style (second
edition): Point Roberts, Washington, Hartley & Marks, 351 pp.

The sound is the same as that of German or Swedish 'oe'. For
English-speakers, the pronunciation can be approximated by placing the
tongue in the position for short 'e' (as in 'fed') or the first part of
long 'a' (as in 'play') and the lips in the position for 'o'. No, this is
not as difficult as it seems at first! If German kids can learn it, so can
you.

The use of the slashed O is not very old; it is based on a spelling reform,
I think in the nineteenth century, whose effect was to make Danish and
Norwegian look less like German on the printed page. I am not sure whether
that was actually the intent. Taxonomists are a conservative bunch, so the
correct way to refer to Moerch is to use the spelling given in the byline
of the article as originally published, not as later reformed. However, if
your typewriter lacks a slashed O or O-umlaut, it is allowable to
substitute OE for it. Danish and German speakers will recognize this as an
older alternative spelling of the same word, but don't substitute an O for
a slashed O. That would change the meaning of some words, sometimes with
unintended humor. Think of how English would look if you substituted a U
for every O, particularly in words like 'sock' and 'flock'.

Fortunately, most word-processing programs now have the capability to add
such symbols to text, and some can even add Greek or Cyrillic symbols.

Cheers,
Andy

Andrew K. Rindsberg
Geological Survey of Alabama