Who were the Igylliones?

From: george knysh
Message: 67672
Date: 2011-06-02

Little bits and pieces while waiting for Pachkova's magnum opus...
The Igylliones are mentioned in Ptolemy's Geography at III,5. They supposedly inhabited the territory east of the Vistula ( and east of the Avarini at the source of the Vistula), and west of the Costoboci and Transmontani. We know the difficulties associated with Ptolemy data, and with his utilization of his many sources. The contextual time frame seems post-Pliny (who localized the Costoboci among the Sarmatians of the Caucasus area).
Question: Is there any way of etymologizing <igylli> as Germanic ? There are similar sounding names, and this could be just coincidence. But if the word has Germanic affinities, then we would have a third internal Bastarnian tribal designation. Any ideas?