Ovid

I re-read the Tristes ( II 191) from Ovid and I get an
interesting passage where something is very strange.

"Iazyges et Colchi Metereaque turba Getaeque Danuvii mediis
vix prohibentur aquis.."
The name "colchi" -so far i know - was a name which described
in generally all the nations from north and east of the Black
Sea. So far I remember we find this name at Vergilius too ( or
was this one Horatius? ).I have here two questions, one from
histroical point of view, an another from lingvistic point of
view:
1) when does the term "colchi" appears for last time in
ancient sources?
2) what chances are there that "colchi" became "volchi" and
later "Vlochi" in the slavic languages?

If there is any chance for the transformation C>B or C>V in
slavic languages, then we have no dificulty anmore because
"ol">"lo" in slavics without troubles., then I guess there is
a very interesting path.

regards

a. moeller