Northwestern Tasmanian is poorly attested from four word lists: The "west coast" vocabularies of Charles Robinson and George Augustus Robinson, with 246 words combined; the Robbins Island list of George Augustus Robinson, with 162 words; and the Macquarie Harbour vocabularies of Allan Cunningham (222 words), collected in 1819.[3]
The list collected by George Augustus Robinson at West Point ("Western Tribes") is divergent, and falls out as a separate language in Bowern. However, it includes only 28 words, so little can be definitively said.