Yes, I thought about the Niemen too, given the directionality of Pliny's listing. Plus, one ancient name for the lower Oder was Ptolemy's Ouiadou(as), convincingly etymologised as *wi-adu- 'forking channel'. As for Guthalus, with a single attestation of the name and the uncertain identification of the river I simply can't propose a good etymology (<th> suggests Germanic, but the form may be garbled to an unknown extent, or reported through a Germanic medium, or whatever). Guthalus doesn't resemble "Old European" hydronyms, but I'll have a look at the old hydronymy of the eastern Baltic region and return to the topic if there's anything worth reporting.
----- Original Message -----
From: danjmi
Sent: Saturday, September 28, 2002 4:59 AM
Subject: [tied] Re: Pliny's "Guthalus"

Why look for a Germanic etymology?
My Grosser Historischer Weltatlas identifies Guthalus with the
Niemen or Memel. That's maybe just a guess, assuming Pliny is
listing rivers east to west, but seems a reasonable one.  This is
getting close to Baltic territory, but anyway isn't the game with the
major rivers of central Europe  "Alteuropaische hydronymik",
looking for a vague I.-E. meaning but pre- any known languages.
Or am I forty or fifty years out of date?
Dan Milton